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Chow JCL, Ruda HE. Mechanisms of Action in FLASH Radiotherapy: A Comprehensive Review of Physicochemical and Biological Processes on Cancerous and Normal Cells. Cells 2024; 13:835. [PMID: 38786057 PMCID: PMC11120005 DOI: 10.3390/cells13100835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 05/09/2024] [Accepted: 05/11/2024] [Indexed: 05/25/2024] Open
Abstract
The advent of FLASH radiotherapy (FLASH-RT) has brought forth a paradigm shift in cancer treatment, showcasing remarkable normal cell sparing effects with ultra-high dose rates (>40 Gy/s). This review delves into the multifaceted mechanisms underpinning the efficacy of FLASH effect, examining both physicochemical and biological hypotheses in cell biophysics. The physicochemical process encompasses oxygen depletion, reactive oxygen species, and free radical recombination. In parallel, the biological process explores the FLASH effect on the immune system and on blood vessels in treatment sites such as the brain, lung, gastrointestinal tract, skin, and subcutaneous tissue. This review investigated the selective targeting of cancer cells and the modulation of the tumor microenvironment through FLASH-RT. Examining these mechanisms, we explore the implications and challenges of integrating FLASH-RT into cancer treatment. The potential to spare normal cells, boost the immune response, and modify the tumor vasculature offers new therapeutic strategies. Despite progress in understanding FLASH-RT, this review highlights knowledge gaps, emphasizing the need for further research to optimize its clinical applications. The synthesis of physicochemical and biological insights serves as a comprehensive resource for cell biology, molecular biology, and biophysics researchers and clinicians navigating the evolution of FLASH-RT in cancer therapy.
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Affiliation(s)
- James C. L. Chow
- Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1X6, Canada
- Department of Radiation Oncology, University of Toronto, Toronto, ON M5T 1P5, Canada
| | - Harry E. Ruda
- Centre of Advance Nanotechnology, Faculty of Applied Science and Engineering, University of Toronto, Toronto, ON M5S 3E4, Canada;
- Department of Materials Science and Engineering, University of Toronto, Toronto, ON M5S 3E4, Canada
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Horst F, Bodenstein E, Brand M, Hans S, Karsch L, Lessmann E, Löck S, Schürer M, Pawelke J, Beyreuther E. Dose and dose rate dependence of the tissue sparing effect at ultra-high dose rate studied for proton and electron beams using the zebrafish embryo model. Radiother Oncol 2024; 194:110197. [PMID: 38447870 DOI: 10.1016/j.radonc.2024.110197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 02/16/2024] [Accepted: 02/26/2024] [Indexed: 03/08/2024]
Abstract
PURPOSE A better characterization of the dependence of the tissue sparing effect at ultra-high dose rate (UHDR) on physical beam parameters (dose, dose rate, radiation quality) would be helpful towards a mechanistic understanding of the FLASH effect and for its broader clinical translation. To address this, a comprehensive study on the normal tissue sparing at UHDR using the zebrafish embryo (ZFE) model was conducted. METHODS One-day-old ZFE were irradiated over a wide dose range (15-95 Gy) in three different beams (proton entrance channel, proton spread out Bragg peak and 30 MeV electrons) at UHDR and reference dose rate. After irradiation the ZFE were incubated for 4 days and then analyzed for four different biological endpoints (pericardial edema, curved spine, embryo length and eye diameter). RESULTS Dose-effect curves were obtained and a sparing effect at UHDR was observed for all three beams. It was demonstrated that proton relative biological effectiveness and UHDR sparing are both relevant to predict the resulting dose response. Dose dependent FLASH modifying factors (FMF) for ZFE were found to be compatible with rodent data from the literature. It was found that the UHDR sparing effect saturates at doses above ∼ 50 Gy with an FMF of ∼ 0.7-0.8. A strong dose rate dependence of the tissue sparing effect in ZFE was observed. The magnitude of the maximum sparing effect was comparable for all studied biological endpoints. CONCLUSION The ZFE model was shown to be a suitable pre-clinical high-throughput model for radiobiological studies on FLASH radiotherapy, providing results comparable to rodent models. This underlines the relevance of ZFE studies for FLASH radiotherapy research.
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Affiliation(s)
- Felix Horst
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany; OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany
| | - Elisabeth Bodenstein
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany; OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany
| | - Michael Brand
- Center for Regenerative Therapies TU Dresden and Cluster of Excellence 'Physics of Life', Technische Universität Dresden, Dresden, Germany
| | - Stefan Hans
- Center for Regenerative Therapies TU Dresden and Cluster of Excellence 'Physics of Life', Technische Universität Dresden, Dresden, Germany
| | - Leonhard Karsch
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany; OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany
| | - Elisabeth Lessmann
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiation Physics, Dresden, Germany
| | - Steffen Löck
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany; Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany; German Cancer Consortium (DKTK), Partner Site Dresden, and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Michael Schürer
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany; National Center for Tumor Diseases Dresden (NCT/UCC), Germany: German Cancer Research Center (DKFZ), Heidelberg, Germany; Faculty of Medicine and University Hospital Carl Gustav Carus, TUD Dresden University of Technology, Dresden, Germany; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden, Germany
| | - Jörg Pawelke
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany; OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany
| | - Elke Beyreuther
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany; Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiation Physics, Dresden, Germany.
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Lövgren N, Fagerström Kristensen I, Petersson K. Feasibility and constraints of Bragg peak FLASH proton therapy treatment planning. Front Oncol 2024; 14:1369065. [PMID: 38737902 PMCID: PMC11082391 DOI: 10.3389/fonc.2024.1369065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 04/02/2024] [Indexed: 05/14/2024] Open
Abstract
Introduction FLASH proton therapy (FLASH-PT) requires ultra-high dose rate (≥ 40 Gy/s) protons to be delivered in a short timescale whilst conforming to a patient-specific target. This study investigates the feasibility and constraints of Bragg peak FLASH-PT treatment planning, and compares the in silico results produced to plans for intensity modulated proton therapy (IMPT). Materials and method Bragg peak FLASH-PT and IMPT treatment plans were generated for bone (n=3), brain (n=3), and lung (n=4) targets using the MIROpt research treatment planning system and the Conformal FLASH library developed by Applications SA from the open-source version of UCLouvain. FLASH-PT beams were simulated using monoenergetic spot-scanned protons traversing through a conformal energy modulator, a range shifter, and an aperture. A dose rate constraint of ≥ 40 Gy/s was included in each FLASH-PT plan optimisation. Results Space limitations in the FLASH-PT adapted beam nozzle imposed a maximum target width constraint, excluding 4 cases from the study. FLASH-PT plans did not satisfy the imposed target dose constraints (D95% ≥ 95% and D2%≤ 105%) but achieved clinically acceptable doses to organs at risk (OARs). IMPT plans adhered to all target and OAR dose constraints. FLASH-PT plans showed a reduction in both target homogeneity (p < 0.001) and dose conformity (non-significant) compared to IMPT. Conclusion Without accounting for a sparing effect, IMPT plans were superior in target coverage, dose conformity, target homogeneity, and OAR sparing compared to FLASH-PT. Further research is warranted in treatment planning optimisation and beam delivery for clinical implementation of Bragg peak FLASH-PT.
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Affiliation(s)
- Nathalie Lövgren
- Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford, United Kingdom
| | - Ingrid Fagerström Kristensen
- Clinical Oncology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
- Department of Haematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Kristoffer Petersson
- Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford, United Kingdom
- Department of Haematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
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Tang R, Yin J, Liu Y, Xue J. FLASH radiotherapy: A new milestone in the field of cancer radiotherapy. Cancer Lett 2024; 587:216651. [PMID: 38342233 DOI: 10.1016/j.canlet.2024.216651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 11/03/2023] [Accepted: 01/13/2024] [Indexed: 02/13/2024]
Abstract
Radiotherapy plays a pivotal role in the control and eradication of tumors, but it can also induce radiation injury to surrounding normal tissues while targeting tumor cells. In recent years, FLASH-Radiotherapy (FLASH-RT) has emerged as a cutting-edge research focus in the field of radiation therapy. By delivering high radiation doses to the treatment target in an ultra-short time, FLASH-RT produces the FLASH effect, which reduces the toxicity to normal tissues while achieving comparable tumor control efficacy to conventional radiotherapy. This review provides a brief overview of the development history of FLASH-RT and its impact on tumor control. Additionally, it focuses on introducing the protective effects and molecular mechanisms of this technology on various normal tissues, as well as exploring its synergistic effects when combined with other tumor therapies. Importantly, this review discusses the challenges faced in translating FLASH-RT into clinical practice and outlines its promising future applications.
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Affiliation(s)
- Rui Tang
- Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, 610072, Sichuan, China; Division of Thoracic Tumor Multimodality Treatment, Cancer Center, The National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Jianqiong Yin
- Division of Thoracic Tumor Multimodality Treatment, Cancer Center, The National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Yuanxin Liu
- Division of Thoracic Tumor Multimodality Treatment, Cancer Center, The National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Jianxin Xue
- Division of Thoracic Tumor Multimodality Treatment, Cancer Center, The National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China; Department of Radiation Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China; Laboratory of Clinical Cell Therapy, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China; Disaster Medical Center, Sichuan University, Chengdu, 610041, Sichuan, China.
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Cengel KA, Kim MM, Diffenderfer ES, Busch TM. FLASH Radiotherapy: What Can FLASH's Ultra High Dose Rate Offer to the Treatment of Patients With Sarcoma? Semin Radiat Oncol 2024; 34:218-228. [PMID: 38508786 DOI: 10.1016/j.semradonc.2024.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/22/2024]
Abstract
FLASH is an emerging treatment paradigm in radiotherapy (RT) that utilizes ultra-high dose rates (UHDR; >40 Gy)/s) of radiation delivery. Developing advances in technology support the delivery of UHDR using electron and proton systems, as well as some ion beam units (eg, carbon ions), while methods to achieve UHDR with photons are under investigation. The major advantage of FLASH RT is its ability to increase the therapeutic index for RT by shifting the dose response curve for normal tissue toxicity to higher doses. Numerous preclinical studies have been conducted to date on FLASH RT for murine sarcomas, alongside the investigation of its effects on relevant normal tissues of skin, muscle, and bone. The tumor control achieved by FLASH RT of sarcoma models is indistinguishable from that attained by treatment with standard RT to the same total dose. FLASH's high dose rates are able to mitigate the severity or incidence of RT side effects on normal tissues as evaluated by endpoints ranging from functional sparing to histological damage. Large animal studies and clinical trials of canine patients show evidence of skin sparing by FLASH vs. standard RT, but also caution against delivery of high single doses with FLASH that exceed those safely applied with standard RT. Also, a human clinical trial has shown that FLASH RT can be delivered safely to bone metastasis. Thus, data to date support continued investigations of clinical translation of FLASH RT for the treatment of patients with sarcoma. Toward this purpose, hypofractionated irradiation schemes are being investigated for FLASH effects on sarcoma and relevant normal tissues.
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Affiliation(s)
- Keith A Cengel
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania..
| | - Michele M Kim
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Eric S Diffenderfer
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Theresa M Busch
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
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Almeida A, Godfroid C, Leavitt RJ, Montay-Gruel P, Petit B, Romero J, Ollivier J, Meziani L, Sprengers K, Paisley R, Grilj V, Limoli CL, Romero P, Vozenin MC. Antitumor Effect by Either FLASH or Conventional Dose Rate Irradiation Involves Equivalent Immune Responses. Int J Radiat Oncol Biol Phys 2024; 118:1110-1122. [PMID: 37951550 PMCID: PMC11093276 DOI: 10.1016/j.ijrobp.2023.10.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 10/05/2023] [Accepted: 10/14/2023] [Indexed: 11/14/2023]
Abstract
PURPOSE The capability of ultrahigh dose rate FLASH radiation therapy to generate the FLASH effect has opened the possibility to enhance the therapeutic index of radiation therapy. The contribution of the immune response has frequently been hypothesized to account for a certain fraction of the antitumor efficacy and tumor kill of FLASH but has yet to be rigorously evaluated. METHODS AND MATERIALS To investigate the immune response as a potentially important mechanism of the antitumor effect of FLASH, various murine tumor models were grafted either subcutaneously or orthotopically into immunocompetent mice or in moderately and severely immunocompromised mice. Mice were locally irradiated with single dose (20 Gy) or hypofractionated regimens (3 × 8 or 2 × 6 Gy) using FLASH (≥2000 Gy/s) and conventional (CONV) dose rates (0.1 Gy/s), with/without anti-CTLA-4. Tumor growth was monitored over time and immune profiling performed. RESULTS FLASH and CONV 20 Gy were isoeffective in delaying tumor growth in immunocompetent and moderately immunodeficient hosts and increased tumor doubling time to >14 days versus >7 days in control animals. Similar observations were obtained with a hypofractionated scheme, regardless of the microenvironment (subcutaneous flank vs ortho lungs). Interestingly, in profoundly immunocompromised mice, 20 Gy FLASH retained antitumor activity and significantly increased tumor doubling time to >14 days versus >8 days in control animals, suggesting a possible antitumor mechanism independent of the immune response. Analysis of the tumor microenvironment showed similar immune profiles after both irradiation modalities with significant decrease of lymphoid cells by ∼40% and a corresponding increase of myeloid cells. In addition, FLASH and CONV did not increase transforming growth factor-β1 levels in tumors compared with unirradiated control animals. Furthermore, when a complete and long-lasting antitumor response was obtained (>140 days), both modalities of irradiation were able to generate a long-term immunologic memory response. CONCLUSIONS The present results clearly document that the tumor responses across multiple immunocompetent and immunodeficient mouse models are largely dose rate independent and simultaneously contradict a major role of the immune response in the antitumor efficacy of FLASH. Therefore, our study indicates that FLASH is as potent as CONV in modulating antitumor immune response and can be used as an immunomodulatory agent.
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Affiliation(s)
- Aymeric Almeida
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Céline Godfroid
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland; Department of Oncology UNIL CHUV, University of Lausanne, Épalinges, Switzerland
| | - Ron J Leavitt
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Pierre Montay-Gruel
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland; Radiation Oncology Department, Iridium Netwerk, Wilrijk (Antwerp), Belgium; Antwerp Research in Radiation Oncology (AReRO), Centre for Oncological Research (CORE), University of Antwerp, Antwerp, Belgium
| | - Benoit Petit
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Jackeline Romero
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Jonathan Ollivier
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Lydia Meziani
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Kevin Sprengers
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Ryan Paisley
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Veljko Grilj
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Charles L Limoli
- Department of Radiation Oncology, University of California, Irvine, California
| | - Pedro Romero
- Department of Oncology UNIL CHUV, University of Lausanne, Épalinges, Switzerland
| | - Marie-Catherine Vozenin
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland.
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Zeng Y, Li H, Wang W, Liu X, Qin B, Dai S, Pang B, Liu M, Quan H, Yang K, Chang Y, Yang Z. Feasibility study of multiple-energy Bragg peak proton FLASH on a superconducting gantry with large momentum acceptance. Med Phys 2024; 51:2164-2174. [PMID: 38169535 DOI: 10.1002/mp.16932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 11/30/2023] [Accepted: 12/20/2023] [Indexed: 01/05/2024] Open
Abstract
BACKGROUND While the Bragg peak proton beam (BP) is capable of superior target conformity and organs-at-risk sparing than the transmission proton beam (TB), its efficacy in FLASH-RT is hindered by both a slow energy switching process and the beam current. A universal range shifter (URS) can pull back the high-energy proton beam while preserving the beam current. Meanwhile, a superconducting gantry with large momentum acceptance (LMA-SC gantry) enables fast energy switching. PURPOSE This study explores the feasibility of multiple-energy BP FLASH-RT on the LMA-SC gantry. METHOD AND MATERIALS A simultaneous dose and spot map optimization algorithm was developed for BP FLASH-RT treatment planning to improve the dose delivery efficiency. The URS was designed to be 0-27 cm thick, with 1 cm per step. BP plans using the URS were optimized using single-field optimization (SFO) and multiple-field optimization (MFO) for ten prostate cancer patients and ten lung cancer patients. The plan delivery parameters, dose, and dose rate metrics of BP plans were compared to those of TB plans using the parameters of the LMA-SC gantry. RESULTS Compared to TB plans, BP plans significantly reduced MUs by 42.7% (P < 0.001) with SFO and 33.3% (P < 0.001) with MFO for prostate cases. For lung cases, the reduction in MUs was 56.8% (P < 0.001) with SFO and 36.4% (P < 0.001) with MFO. BP plans also outperformed TB plans by reducing mean normal tissue doses. BP-SFO plans achieved a reduction of 56.7% (P < 0.001) for prostate cases and 57.7% (P < 0.001) for lung cases, while BP-MFO plans achieved a reduction of 54.2% (P < 0.001) for the prostate case and 40.0% (P < 0.001) for lung cases. For both TB and BP plans, normal tissues in prostate and lung cases received 100.0% FLASH dose rate coverage (>40 Gy/s). CONCLUSIONS By utilizing the URS and the LMA-SC gantry, it is possible to perform multiple-energy BP FLASH-RT, resulting in better normal tissue sparing, as compared to TB plans.
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Affiliation(s)
- Yiling Zeng
- Department of Medical Physics, School of Physics and Technology, Wuhan University, Wuhan, China
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Laboratory of Precision Radiation Oncology, Wuhan, China
| | - Heng Li
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, Maryland, USA
| | - Wei Wang
- State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Xu Liu
- State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Bin Qin
- State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Shuyang Dai
- School of Mathematics and Statistics, Wuhan University, Wuhan, P. R. China
| | - Bo Pang
- Department of Medical Physics, School of Physics and Technology, Wuhan University, Wuhan, China
| | - Muyu Liu
- Department of Medical Physics, School of Physics and Technology, Wuhan University, Wuhan, China
| | - Hong Quan
- Department of Medical Physics, School of Physics and Technology, Wuhan University, Wuhan, China
| | - Kunyu Yang
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Laboratory of Precision Radiation Oncology, Wuhan, China
| | - Yu Chang
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Laboratory of Precision Radiation Oncology, Wuhan, China
| | - Zhiyong Yang
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Laboratory of Precision Radiation Oncology, Wuhan, China
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Schoenauen L, Stubbe FX, Van Gestel D, Penninckx S, Heuskin AC. C. elegans: A potent model for high-throughput screening experiments investigating the FLASH effect. Clin Transl Radiat Oncol 2024; 45:100712. [PMID: 38125649 PMCID: PMC10731598 DOI: 10.1016/j.ctro.2023.100712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 11/30/2023] [Accepted: 12/06/2023] [Indexed: 12/23/2023] Open
Abstract
This study explores the effects of UHDR irradiation on Caenorhabditis elegans embryos. UHDR proton and electron beams demonstrate a sparing effect, aligning with literature findings. This highlights C. elegans suitability as a screening model for studying the LET impact on the FLASH effect, reinforcing its potential in radiation research.
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Affiliation(s)
- Lucas Schoenauen
- NAmur Research Insitute for Life Sciences, University of Namur, Belgium
| | | | - Dirk Van Gestel
- Department of Radiation Oncology, Institut Jules Bordet, Hopital Universitaire de Bruxelles (HUB), Université Libre de Bruxelles, Brussels, Belgium
| | - Sébastien Penninckx
- Department of Radiation Oncology, Institut Jules Bordet, Hopital Universitaire de Bruxelles (HUB), Université Libre de Bruxelles, Brussels, Belgium
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Sesink A, Becerra M, Ruan JL, Leboucher S, Dubail M, Heinrich S, Jdey W, Petersson K, Fouillade C, Berthault N, Dutreix M, Girard PM. The AsiDNA™ decoy mimicking DSBs protects the normal tissue from radiation toxicity through a DNA-PK/p53/p21-dependent G1/S arrest. NAR Cancer 2024; 6:zcae011. [PMID: 38476631 PMCID: PMC10928987 DOI: 10.1093/narcan/zcae011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 02/01/2024] [Accepted: 02/27/2024] [Indexed: 03/14/2024] Open
Abstract
AsiDNA™, a cholesterol-coupled oligonucleotide mimicking double-stranded DNA breaks, was developed to sensitize tumour cells to radio- and chemotherapy. This drug acts as a decoy hijacking the DNA damage response. Previous studies have demonstrated that standalone AsiDNA™ administration is well tolerated with no additional adverse effects when combined with chemo- and/or radiotherapy. The lack of normal tissue complication encouraged further examination into the role of AsiDNA™ in normal cells. This research demonstrates the radioprotective properties of AsiDNA™. In vitro, AsiDNA™ induces a DNA-PK/p53/p21-dependent G1/S arrest in normal epithelial cells and fibroblasts that is absent in p53 deficient and proficient tumour cells. This cell cycle arrest improved survival after irradiation only in p53 proficient normal cells. Combined administration of AsiDNA™ with conventional radiotherapy in mouse models of late and early radiation toxicity resulted in decreased onset of lung fibrosis and increased intestinal crypt survival. Similar results were observed following FLASH radiotherapy in standalone or combined with AsiDNA™. Mechanisms comparable to those identified in vitro were detected both in vivo, in the intestine and ex vivo, in precision cut lung slices. Collectively, the results suggest that AsiDNA™ can partially protect healthy tissues from radiation toxicity by triggering a G1/S arrest in normal cells.
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Affiliation(s)
- Anouk Sesink
- Institut Curie, Université PSL, CNRS UMR3347, INSERM U1021, 91405 Orsay, France
- Université Paris-Saclay, CNRS UMR 3347, INSERM U1021, 91405 Orsay, France
| | - Margaux Becerra
- Institut Curie, Université PSL, CNRS UMR3347, INSERM U1021, 91405 Orsay, France
- Université Paris-Saclay, CNRS UMR 3347, INSERM U1021, 91405 Orsay, France
| | - Jia-Ling Ruan
- Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, UK
| | - Sophie Leboucher
- Histology platform, Institut Curie, CNRS UMR3348, 91405 Orsay, France
| | - Maxime Dubail
- Institut Curie, Université PSL, CNRS UMR3347, INSERM U1021, 91405 Orsay, France
- Université Paris-Saclay, CNRS UMR 3347, INSERM U1021, 91405 Orsay, France
| | - Sophie Heinrich
- Institut Curie, Université PSL, CNRS UMR3347, INSERM U1021, 91405 Orsay, France
- Université Paris-Saclay, CNRS UMR 3347, INSERM U1021, 91405 Orsay, France
| | - Wael Jdey
- Valerio Therapeutics, 49 Bd du Général Martial Valin, 75015 Paris, France
| | - Kristoffer Petersson
- Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, UK
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund University, Lund, Sweden
| | - Charles Fouillade
- Institut Curie, Université PSL, CNRS UMR3347, INSERM U1021, 91405 Orsay, France
- Université Paris-Saclay, CNRS UMR 3347, INSERM U1021, 91405 Orsay, France
| | - Nathalie Berthault
- Institut Curie, Université PSL, CNRS UMR3347, INSERM U1021, 91405 Orsay, France
- Université Paris-Saclay, CNRS UMR 3347, INSERM U1021, 91405 Orsay, France
| | - Marie Dutreix
- Institut Curie, Université PSL, CNRS UMR3347, INSERM U1021, 91405 Orsay, France
- Université Paris-Saclay, CNRS UMR 3347, INSERM U1021, 91405 Orsay, France
| | - Pierre-Marie Girard
- Institut Curie, Université PSL, CNRS UMR3347, INSERM U1021, 91405 Orsay, France
- Université Paris-Saclay, CNRS UMR 3347, INSERM U1021, 91405 Orsay, France
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10
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Borghini A, Labate L, Piccinini S, Panaino CMV, Andreassi MG, Gizzi LA. FLASH Radiotherapy: Expectations, Challenges, and Current Knowledge. Int J Mol Sci 2024; 25:2546. [PMID: 38473799 DOI: 10.3390/ijms25052546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 02/12/2024] [Accepted: 02/19/2024] [Indexed: 03/14/2024] Open
Abstract
Major strides have been made in the development of FLASH radiotherapy (FLASH RT) in the last ten years, but there are still many obstacles to overcome for transfer to the clinic to become a reality. Although preclinical and first-in-human clinical evidence suggests that ultra-high dose rates (UHDRs) induce a sparing effect in normal tissue without modifying the therapeutic effect on the tumor, successful clinical translation of FLASH-RT depends on a better understanding of the biological mechanisms underpinning the sparing effect. Suitable in vitro studies are required to fully understand the radiobiological mechanisms associated with UHDRs. From a technical point of view, it is also crucial to develop optimal technologies in terms of beam irradiation parameters for producing FLASH conditions. This review provides an overview of the research progress of FLASH RT and discusses the potential challenges to be faced before its clinical application. We critically summarize the preclinical evidence and in vitro studies on DNA damage following UHDR irradiation. We also highlight the ongoing developments of technologies for delivering FLASH-compliant beams, with a focus on laser-driven plasma accelerators suitable for performing basic radiobiological research on the UHDR effects.
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Affiliation(s)
| | - Luca Labate
- Intense Laser Irradiation Laboratory (ILIL), CNR Istituto Nazionale di Ottica, 56124 Pisa, Italy
| | - Simona Piccinini
- Intense Laser Irradiation Laboratory (ILIL), CNR Istituto Nazionale di Ottica, 56124 Pisa, Italy
| | | | | | - Leonida Antonio Gizzi
- Intense Laser Irradiation Laboratory (ILIL), CNR Istituto Nazionale di Ottica, 56124 Pisa, Italy
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11
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Padilla O, Minns HE, Wei HJ, Fan W, Webster-Carrion A, Tazhibi M, McQuillan NM, Zhang X, Gallitto M, Yeh R, Zhang Z, Hei TK, Szalontay L, Pavisic J, Tan Y, Deoli N, Garty G, Garvin JH, Canoll PD, Vanpouille-Box C, Menon V, Olah M, Rabadan R, Wu CC, Gartrell RD. Immune Response following FLASH and Conventional Radiation in Diffuse Midline Glioma. Int J Radiat Oncol Biol Phys 2024:S0360-3016(24)00300-6. [PMID: 38364947 DOI: 10.1016/j.ijrobp.2024.01.219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 01/15/2024] [Accepted: 01/28/2024] [Indexed: 02/18/2024]
Abstract
PURPOSE Diffuse midline glioma (DMG) is a fatal tumor traditionally treated with radiation therapy (RT) and previously characterized as having a noninflammatory tumor immune microenvironment (TIME). FLASH is a novel RT technique using ultra-high dose rate that is associated with decreased toxicity and effective tumor control. However, the effect of FLASH and conventional (CONV) RT on the DMG TIME has not yet been explored. METHODS AND MATERIALS Here, we performed single-cell RNA sequencing (scRNA-seq) and flow cytometry on immune cells isolated from an orthotopic syngeneic murine model of brainstem DMG after the use of FLASH (90 Gy/sec) or CONV (2 Gy/min) dose-rate RT and compared to unirradiated tumor (SHAM). RESULTS At day 4 post-RT, FLASH exerted similar effects as CONV in the predominant microglial (MG) population, including the presence of two activated subtypes. However, at day 10 post-RT, we observed a significant increase in the type 1 interferon α/β receptor (IFNAR+) in MG in CONV and SHAM compared to FLASH. In the non-resident myeloid clusters of macrophages (MACs) and dendritic cells (DCs), we found increased type 1 interferon (IFN1) pathway enrichment for CONV compared to FLASH and SHAM by scRNA-seq. We observed this trend by flow cytometry at day 4 post-RT in IFNAR+ MACs and DCs, which equalized by day 10 post-RT. DMG control and murine survival were equivalent between RT dose rates. CONCLUSIONS Our work is the first to map CONV and FLASH immune alterations of the DMG TIME with single-cell resolution. Although DMG tumor control and survival were similar between CONV and FLASH, we found that changes in immune compartments differed over time. Importantly, although both RT modalities increased IFN1, we found that the timing of this response was cell-type and dose-rate dependent. These temporal differences, particularly in the context of tumor control, warrant further study.
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Affiliation(s)
- Oscar Padilla
- Department of Radiation Oncology, Columbia University Irving Medical Center, New York, New York; Department of Radiation Oncology, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Hanna E Minns
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York; Oregon Health and Science University School of Medicine, Portland, Oregon
| | - Hong-Jian Wei
- Department of Radiation Oncology, Columbia University Irving Medical Center, New York, New York
| | - Weijia Fan
- Mailman School of Public Health, Columbia University, New York, New York
| | | | - Masih Tazhibi
- Department of Radiation Oncology, Columbia University Irving Medical Center, New York, New York
| | - Nicholas M McQuillan
- Department of Radiation Oncology, Columbia University Irving Medical Center, New York, New York
| | - Xu Zhang
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York; Institute for Cancer Genetics, Columbia University Irving Medical Center, New York, New York; Department of Genetics and Development, Columbia University Irving Medical Center, New York, New York
| | - Matthew Gallitto
- Department of Radiation Oncology, Columbia University Irving Medical Center, New York, New York
| | - Rebecca Yeh
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York
| | - Zhiguo Zhang
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York; Institute for Cancer Genetics, Columbia University Irving Medical Center, New York, New York; Department of Genetics and Development, Columbia University Irving Medical Center, New York, New York
| | - Tom K Hei
- Department of Radiation Oncology, Columbia University Irving Medical Center, New York, New York; Center for Radiological Research, Columbia University Irving Medical Center, New York, New York
| | - Luca Szalontay
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York
| | - Jovana Pavisic
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York
| | - Yuewen Tan
- Radiological Research Accelerator Facility, Columbia University Irving Medical Center, Irvington, New York
| | - Naresh Deoli
- Radiological Research Accelerator Facility, Columbia University Irving Medical Center, Irvington, New York
| | - Guy Garty
- Department of Radiation Oncology, Columbia University Irving Medical Center, New York, New York; Center for Radiological Research, Columbia University Irving Medical Center, New York, New York; Radiological Research Accelerator Facility, Columbia University Irving Medical Center, Irvington, New York
| | - James H Garvin
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York
| | - Peter D Canoll
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York
| | | | - Vilas Menon
- Department of Neurology, Columbia University Irving Medical Center, New York, New York; Center for Translational and Computational Neuroimmunology, Columbia University Irving Medical Center, New York, New York; Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York, New York
| | - Marta Olah
- Department of Neurology, Columbia University Irving Medical Center, New York, New York; Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York, New York
| | - Raul Rabadan
- Department of Systems Biology, Columbia University Irving Medical Center, New York, New York; Department of Biomedical Informatics, Columbia University Irving Medical Center, New York, New York; Program for Mathematical Genomics, Columbia University Irving Medical Center, New York, New York
| | - Cheng-Chia Wu
- Department of Radiation Oncology, Columbia University Irving Medical Center, New York, New York
| | - Robyn D Gartrell
- Department of Pediatrics, Columbia University Irving Medical Center, New York, New York; Department of Oncology, Division of Pediatric Oncology, Johns Hopkins School of Medicine, Baltimore, Maryland.
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12
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Kim K, Kim MM, Skoufos G, Diffenderfer ES, Motlagh SAO, Kokkorakis M, Koliaki I, Morcos G, Shoniyozov K, Griffin J, Hatzigeorgiou AG, Metz JM, Lin A, Feigenberg SJ, Cengel KA, Ky B, Koumenis C, Verginadis II. FLASH Proton Radiation Therapy Mitigates Inflammatory and Fibrotic Pathways and Preserves Cardiac Function in a Preclinical Mouse Model of Radiation-Induced Heart Disease. Int J Radiat Oncol Biol Phys 2024:S0360-3016(24)00301-8. [PMID: 38364948 DOI: 10.1016/j.ijrobp.2024.01.224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 01/12/2024] [Accepted: 01/28/2024] [Indexed: 02/18/2024]
Abstract
PURPOSE Studies during the past 9 years suggest that delivering radiation at dose rates exceeding 40 Gy/s, known as "FLASH" radiation therapy, enhances the therapeutic index of radiation therapy (RT) by decreasing normal tissue damage while maintaining tumor response compared with conventional (or standard) RT. This study demonstrates the cardioprotective benefits of FLASH proton RT (F-PRT) compared with standard (conventional) proton RT (S-PRT), as evidenced by reduced acute and chronic cardiac toxicities. METHODS AND MATERIALS Mice were imaged using cone beam computed tomography to precisely determine the heart's apex as the beam isocenter. Irradiation was conducted using a shoot-through technique with a 5-mm diameter circular collimator. Bulk RNA-sequencing was performed on nonirradiated samples, as well as apexes treated with F-PRT or S-PRT, at 2 weeks after a single 40 Gy dose. Inflammatory responses were assessed through multiplex cytokine/chemokine microbead assay and immunofluorescence analyses. Levels of perivascular fibrosis were quantified using Masson's Trichrome and Picrosirius red staining. Additionally, cardiac tissue functionality was evaluated by 2-dimensional echocardiograms at 8- and 30-weeks post-PRT. RESULTS Radiation damage was specifically localized to the heart's apex. RNA profiling of cardiac tissues treated with PRT revealed that S-PRT uniquely upregulated pathways associated with DNA damage response, induction of tumor necrosis factor superfamily, and inflammatory response, and F-PRT primarily affected cytoplasmic translation, mitochondrion organization, and adenosine triphosphate synthesis. Notably, F-PRT led to a milder inflammatory response, accompanied by significantly attenuated changes in transforming growth factor β1 and α smooth muscle actin levels. Critically, F-PRT decreased collagen deposition and better preserved cardiac functionality compared with S-PRT. CONCLUSIONS This study demonstrated that F-PRT reduces the induction of an inflammatory environment with lower expression of inflammatory cytokines and profibrotic factors. Importantly, the results indicate that F-PRT better preserves cardiac functionality, as confirmed by echocardiography analysis, while also mitigating the development of long-term fibrosis.
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Affiliation(s)
- Kyle Kim
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Michele M Kim
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Giorgos Skoufos
- Department of Electrical & Computer Engineering, University of Thessaly, Greece; Hellenic Pasteur Institute, Athens, Greece
| | - Eric S Diffenderfer
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Seyyedeh Azar Oliaei Motlagh
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Michail Kokkorakis
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Ilektra Koliaki
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - George Morcos
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Khayrullo Shoniyozov
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Joanna Griffin
- Department of Medicine, Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Artemis G Hatzigeorgiou
- Department of Electrical & Computer Engineering, University of Thessaly, Greece; Hellenic Pasteur Institute, Athens, Greece; DIANA-Laboratory, Department of Computer Science and Biomedical Informatics, University of Thessaly, Thessaly, Greece
| | - James M Metz
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Alexander Lin
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Steven J Feigenberg
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Keith A Cengel
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Bonnie Ky
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Constantinos Koumenis
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.
| | - Ioannis I Verginadis
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.
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13
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Miles D, Sforza D, Wong J, Rezaee M. Dosimetric characterization of a rotating anode x-ray tube for FLASH radiotherapy research. Med Phys 2024; 51:1474-1483. [PMID: 37458068 PMCID: PMC10792113 DOI: 10.1002/mp.16609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 05/16/2023] [Accepted: 06/20/2023] [Indexed: 07/18/2023] Open
Abstract
PURPOSE Most current research toward ultra-high dose rate (FLASH) radiation is conducted with advanced proton and electron accelerators, which are of limited accessibility to basic laboratory research. An economical alternative to charged particle accelerators is to employ high-capacity rotating anode x-ray tubes to produce kilovoltage x-rays at FLASH dose rates at short source-to-surface distances (SSD). This work describes a comprehensive dosimetric evaluation of a rotating anode x-ray tube for potential application in laboratory FLASH study. METHODS AND MATERIALS A commercially available high-capacity fluoroscopy x-ray tube with 75 kW input power was implemented as a potential FLASH irradiator. Radiochromic EBT3 film and thermoluminescent dosimeters (TLDs) were used to investigate the effects of SSD and field size on dose rates and depth-dose characteristics in kV-compatible solid water phantoms. Custom 3D printed accessories were developed to enable reproducible phantom setup at very short SSD. Open and collimated radiation fields were assessed. RESULTS Despite the lower x-ray energy and short SSD used, FLASH dose rates above 40 Gy/s were achieved for targets up to 10-mm depth in solid water. Maximum surface dose rates of 96 Gy/s were measured in the open field at 47 mm SSD. A non-uniform high-to-low dose gradient was observed in the planar dose distribution, characteristic of anode heel effects. With added collimation, beams up to 10-mm diameter with reasonable uniformity can be produced. Typical 80%-20% penumbra in the collimated x-ray FLASH beams were less than 1 mm at 5-mm depth in phantom. Ramp-up times at the maximum input current were less than 1 ms. CONCLUSION Our dosimetric characterization demonstrates that rotating anode x-ray tube technology is capable of producing radiation beams in support of preclinical FLASH radiobiology research.
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Affiliation(s)
- Devin Miles
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, 21231 MD, USA
| | - Daniel Sforza
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, 21231 MD, USA
| | - John Wong
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, 21231 MD, USA
| | - Mohammad Rezaee
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, 21231 MD, USA
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14
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Rudigkeit S, Schmid TE, Dombrowsky AC, Stolz J, Bartzsch S, Chen CB, Matejka N, Sammer M, Bergmaier A, Dollinger G, Reindl J. Proton-FLASH: effects of ultra-high dose rate irradiation on an in-vivo mouse ear model. Sci Rep 2024; 14:1418. [PMID: 38228747 PMCID: PMC10791610 DOI: 10.1038/s41598-024-51951-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 01/11/2024] [Indexed: 01/18/2024] Open
Abstract
FLASH-radiotherapy may provide significant sparing of healthy tissue through ultra-high dose rates in protons, electrons, and x-rays while maintaining the tumor control. Key factors for the FLASH effect might be oxygen depletion, the immune system, and the irradiated blood volume, but none could be fully confirmed yet. Therefore, further investigations are necessary. We investigated the protective (tissue sparing) effect of FLASH in proton treatment using an in-vivo mouse ear model. The right ears of Balb/c mice were irradiated with 20 MeV protons at the ion microprobe SNAKE in Garching near Munich by using three dose rates (Conv = 0.06 Gy/s, Flash9 = 9.3 Gy/s and Flash930 = 930 Gy/s) at a total dose of 23 Gy or 33 Gy. The ear thickness, desquamation, and erythema combined in an inflammation score were measured for 180 days. The cytokines TGF-β1, TNF-α, IL1α, and IL1β were analyzed in the blood sampled in the first 4 weeks and at termination day. No differences in inflammation reactions were visible in the 23 Gy group for the different dose rates. In the 33 Gy group, the ear swelling and the inflammation score for Flash9 was reduced by (57 ± 12) % and (67 ± 17) % and for Flash930 by (40 ± 13) % and (50 ± 17) % compared to the Conv dose rate. No changes in the cytokines in the blood could be measured. However, an estimation of the irradiated blood volume demonstrates, that 100-times more blood is irradiated when using Conv compared to using Flash9 or Flash930. This indicates that blood might play a role in the underlying mechanisms in the protective effect of FLASH.
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Affiliation(s)
- Sarah Rudigkeit
- Institute of Applied Physics and Measurement Technologies, Universität der Bundeswehr München, Neubiberg, Germany
| | - Thomas E Schmid
- Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany
- Department of Radiooncology, School of Medicine, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany
| | - Annique C Dombrowsky
- Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany
| | - Jessica Stolz
- Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany
| | - Stefan Bartzsch
- Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany
- Department of Radiooncology, School of Medicine, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany
| | - Ce-Belle Chen
- Centre for Ion Beam Applications, Department of Physics, National University of Singapore, Singapore, Singapore
- Singapore Synchrotron Light Source, National University of Singapore, Singapore, Singapore
| | - Nicole Matejka
- Institute of Applied Physics and Measurement Technologies, Universität der Bundeswehr München, Neubiberg, Germany
| | - Matthias Sammer
- Institute of Applied Physics and Measurement Technologies, Universität der Bundeswehr München, Neubiberg, Germany
| | - Andreas Bergmaier
- Institute of Applied Physics and Measurement Technologies, Universität der Bundeswehr München, Neubiberg, Germany
| | - Günther Dollinger
- Institute of Applied Physics and Measurement Technologies, Universität der Bundeswehr München, Neubiberg, Germany
| | - Judith Reindl
- Institute of Applied Physics and Measurement Technologies, Universität der Bundeswehr München, Neubiberg, Germany.
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15
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Yin L, Masumi U, Ota K, Sforza DM, Miles D, Rezaee M, Wong JW, Jia X, Li H. Feasibility of Synchrotron-Based Ultra-High Dose Rate (UHDR) Proton Irradiation with Pencil Beam Scanning for FLASH Research. Cancers (Basel) 2024; 16:221. [PMID: 38201648 PMCID: PMC10778151 DOI: 10.3390/cancers16010221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 12/12/2023] [Accepted: 12/15/2023] [Indexed: 01/12/2024] Open
Abstract
BACKGROUND This study aims to present the feasibility of developing a synchrotron-based proton ultra-high dose rate (UHDR) pencil beam scanning (PBS) system. METHODS The RF extraction power in the synchrotron system was increased to generate 142.4 MeV pulsed proton beams for UHDR irradiation at ~100 nA beam current. The charge per spill was measured using a Faraday cup. The spill length and microscopic time structure of each spill was measured with a 2D strip transmission ion chamber. The measured UHDR beam fluence was used to derive the spot dwell time for pencil beam scanning. Absolute dose distributions at various depths and spot spacings were measured using Gafchromic films in a solid-water phantom. RESULTS For proton UHDR beams at 142.4 MeV, the maximum charge per spill is 4.96 ± 0.10 nC with a maximum spill length of 50 ms. This translates to an average beam current of approximately 100 nA during each spill. Using a 2 × 2 spot delivery pattern, the delivered dose per spill at 5 cm and 13.5 cm depth is 36.3 Gy (726.3 Gy/s) and 56.2 Gy (1124.0 Gy/s), respectively. CONCLUSIONS The synchrotron-based proton therapy system has the capability to deliver pulsed proton UHDR PBS beams. The maximum deliverable dose and field size per pulse are limited by the spill length and extraction charge.
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Affiliation(s)
- Lingshu Yin
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; (D.M.S.); (D.M.); (M.R.); (J.W.W.); (X.J.); (H.L.)
| | - Umezawa Masumi
- Hitachi, Ltd., Research and Development Group, Center for Technology Innovation–Energy, 7-2-1, Omika-chou, Hitachi-shi 319-1292, Ibaraki-ken, Japan;
| | - Kan Ota
- Pyramid Technical Consultants, Inc., Boston, MA 02452, USA;
| | - Daniel M. Sforza
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; (D.M.S.); (D.M.); (M.R.); (J.W.W.); (X.J.); (H.L.)
| | - Devin Miles
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; (D.M.S.); (D.M.); (M.R.); (J.W.W.); (X.J.); (H.L.)
| | - Mohammad Rezaee
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; (D.M.S.); (D.M.); (M.R.); (J.W.W.); (X.J.); (H.L.)
| | - John W. Wong
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; (D.M.S.); (D.M.); (M.R.); (J.W.W.); (X.J.); (H.L.)
| | - Xun Jia
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; (D.M.S.); (D.M.); (M.R.); (J.W.W.); (X.J.); (H.L.)
| | - Heng Li
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; (D.M.S.); (D.M.); (M.R.); (J.W.W.); (X.J.); (H.L.)
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16
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Almeida A, Togno M, Ballesteros-Zebadua P, Franco-Perez J, Geyer R, Schaefer R, Petit B, Grilj V, Meer D, Safai S, Lomax T, Weber DC, Bailat C, Psoroulas S, Vozenin MC. Dosimetric and biologic intercomparison between electron and proton FLASH beams. Radiother Oncol 2024; 190:109953. [PMID: 37839557 DOI: 10.1016/j.radonc.2023.109953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 10/07/2023] [Accepted: 10/11/2023] [Indexed: 10/17/2023]
Abstract
BACKGROUND AND PURPOSE The FLASH effect has been validated in different preclinical experiments with electrons (eFLASH) and protons (pFLASH) operating at an average dose rate above 40 Gy/s. However, no systematic intercomparison of the FLASH effect produced by eFLASHvs. pFLASH has yet been performed and constitutes the aim of the present study. MATERIALS AND METHODS The electron eRT6/Oriatron/CHUV/5.5 MeV and proton Gantry1/PSI/170 MeV were used to deliver conventional (0.1 Gy/s eCONV and pCONV) and FLASH (≥110 Gy/s eFLASH and pFLASH) dose rates. Protons were delivered in transmission. Dosimetric and biologic intercomparisons were performed using previously validated dosimetric approaches and experimental murine models. RESULTS The difference between the average absorbed dose measured at Gantry 1 with PSI reference dosimeters and with CHUV/IRA dosimeters was -1.9 % (0.1 Gy/s) and + 2.5 % (110 Gy/s). The neurocognitive capacity of eFLASH and pFLASH irradiated mice was indistinguishable from the control, while both eCONV and pCONV irradiated cohorts showed cognitive decrements. Complete tumor response was obtained after an ablative dose of 20 Gy delivered with the two beams at CONV and FLASH dose rates. Tumor rejection upon rechallenge indicates that anti-tumor immunity was activated independently of the beam-type and the dose-rate. CONCLUSION Despite major differences in the temporal microstructure of proton and electron beams, this study shows that dosimetric standards can be established. Normal brain protection and tumor control were produced by the two beams. More specifically, normal brain protection was achieved when a single dose of 10 Gy was delivered in 90 ms or less, suggesting that the most important physical parameter driving the FLASH sparing effect might be the mean dose rate. In addition, a systemic anti-tumor immunological memory response was observed in mice exposed to high ablative dose of electron and proton delivered at CONV and FLASH dose rate.
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Affiliation(s)
- A Almeida
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - M Togno
- Center for Proton Therapy, Paul Scherrer Institute, 5323, Villigen, Switzerland
| | - P Ballesteros-Zebadua
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland; Instituto Nacional de Neurología y Neurocirugía MVS, Mexico City, Mexico
| | - J Franco-Perez
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland; Instituto Nacional de Neurología y Neurocirugía MVS, Mexico City, Mexico
| | - R Geyer
- Department of Radiation Oncology, lnselspital, Bern University Hospital, University of Bern, Switzerland
| | - R Schaefer
- Center for Proton Therapy, Paul Scherrer Institute, 5323, Villigen, Switzerland
| | - B Petit
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - V Grilj
- Institute of Radiation Physics (IRA)/CHUV, Lausanne University Hospital, Lausanne, Switzerland
| | - D Meer
- Center for Proton Therapy, Paul Scherrer Institute, 5323, Villigen, Switzerland
| | - S Safai
- Center for Proton Therapy, Paul Scherrer Institute, 5323, Villigen, Switzerland
| | - T Lomax
- Center for Proton Therapy, Paul Scherrer Institute, 5323, Villigen, Switzerland
| | - D C Weber
- Center for Proton Therapy, Paul Scherrer Institute, 5323, Villigen, Switzerland; Department of Radiation Oncology, lnselspital, Bern University Hospital, University of Bern, Switzerland; Department of Radiation Oncology, University Hospital of Zurich, Switzerland
| | - C Bailat
- Institute of Radiation Physics (IRA)/CHUV, Lausanne University Hospital, Lausanne, Switzerland
| | - S Psoroulas
- Center for Proton Therapy, Paul Scherrer Institute, 5323, Villigen, Switzerland
| | - Marie-Catherine Vozenin
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland; Radiotherapy and Radiobiology sector, Radiation Therapy service, University hospital of Geneva, Geneva, Switzerland.
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17
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Beckers C, Pruschy M, Vetrugno I. Tumor hypoxia and radiotherapy: A major driver of resistance even for novel radiotherapy modalities. Semin Cancer Biol 2024; 98:19-30. [PMID: 38040401 DOI: 10.1016/j.semcancer.2023.11.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 11/16/2023] [Accepted: 11/22/2023] [Indexed: 12/03/2023]
Abstract
Hypoxia in solid tumors is an important predictor of poor clinical outcome to radiotherapy. Both physicochemical and biological processes contribute to a reduced sensitivity of hypoxic tumor cells to ionizing radiation and hypoxia-related treatment resistances. A conventional low-dose fractionated radiotherapy regimen exploits iterative reoxygenation in between the individual fractions, nevertheless tumor hypoxia still remains a major hurdle for successful treatment outcome. The technological advances achieved in image guidance and highly conformal dose delivery make it nowadays possible to prescribe larger doses to the tumor as part of single high-dose or hypofractionated radiotherapy, while keeping an acceptable level of normal tissue complication in the co-irradiated organs at risk. However, we insufficiently understand the impact of tumor hypoxia to single high-doses of RT and hypofractionated RT. So-called FLASH radiotherapy, which delivers ionizing radiation at ultrahigh dose rates (> 40 Gy/sec), has recently emerged as an important breakthrough in the radiotherapy field to reduce normal tissue toxicity compared to irradiation at conventional dose rates (few Gy/min). Not surprisingly, oxygen consumption and tumor hypoxia also seem to play an intriguing role for FLASH radiotherapy. Here we will discuss the role of tumor hypoxia for radiotherapy in general and in the context of novel radiotherapy treatment approaches.
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Affiliation(s)
- Claire Beckers
- Laboratory for Applied Radiobiology, Department of Radiation Oncology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Martin Pruschy
- Laboratory for Applied Radiobiology, Department of Radiation Oncology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.
| | - Irene Vetrugno
- Laboratory for Applied Radiobiology, Department of Radiation Oncology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
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18
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Mascia A, McCauley S, Speth J, Nunez SA, Boivin G, Vilalta M, Sharma RA, Perentesis JP, Sertorio M. Impact of Multiple Beams on the FLASH Effect in Soft Tissue and Skin in Mice. Int J Radiat Oncol Biol Phys 2024; 118:253-261. [PMID: 37541394 DOI: 10.1016/j.ijrobp.2023.07.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 06/19/2023] [Accepted: 07/14/2023] [Indexed: 08/06/2023]
Abstract
PURPOSE FLASH proton pencil beam scanning (p-PBS) showed a reduction in mouse skin toxicity and fibrosis when delivered as a single, uninterrupted, high-dose fraction. Clinical p-PBS treatment usually requires multiple beams to achieve good conformality, and these beams are separated by minutes to allow patient and equipment repositioning. We evaluate the impact of multibeam versus single-beam proton radiation on the FLASH sparing effect on skin toxicity. METHODS AND MATERIALS The right hind leg of 10-week-old female C57Bl/6j mice was irradiated using a Varian ProBeam proton beam scanning gantry system at conventional (1 Gy/s) or FLASH (100 Gy/s) average field dose rate. We scored the skin toxicity after different doses for 7 weeks. The treatment was delivered as 1, 2, or 3 equal beams with an interruption of 2 minutes. For each beam delivery, the equipment remained in the same position so that there was a full overlap of beams administered. RESULTS Single-beam delivery confirmed a benefit for p-PBS FLASH in this model at 30, 35, and 40 Gy. At 30 and 35 Gy, a single beam interruption of 2 minutes (2 × 15 Gy or 2 × 17.5 Gy) reduced the FLASH sparing effect, which remained significant (P < .001). However, 2 interruptions (3 × 10 Gy or 3 × 11.6 Gy) abrogated the normal tissue sparing effect. CONCLUSIONS Our results indicate that the FLASH sparing effect in areas of beam overlap can be compromised by interruptions in delivery time. Time gap between overlapping beams and spatial arrangement of the delivered beams are important parameters for FLASH studies. The effect of multibeam needs to be studied on different organs of interest.
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Affiliation(s)
- Anthony Mascia
- Department of Radiation Oncology, University of Cincinnati College of Medicine, Cincinnati, Ohio; Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Shelby McCauley
- Department of Radiation Oncology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Joseph Speth
- Department of Radiation Oncology, University of Cincinnati College of Medicine, Cincinnati, Ohio; Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Stefanno Alarcon Nunez
- Department of Radiation Oncology, University of Cincinnati College of Medicine, Cincinnati, Ohio; Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Gael Boivin
- Varian, a Siemens Healthineers Company, Palo Alto, California
| | - Marta Vilalta
- Varian, a Siemens Healthineers Company, Palo Alto, California
| | - Ricky A Sharma
- Varian, a Siemens Healthineers Company, Palo Alto, California
| | | | - Mathieu Sertorio
- Department of Radiation Oncology, University of Cincinnati College of Medicine, Cincinnati, Ohio; Department of Radiation Oncology, University of Cincinnati Cancer Center, University of Cincinnati College of Medicine, Cincinnati, Ohio.
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19
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Miles D, Sforza D, Wong JW, Gabrielson K, Aziz K, Mahesh M, Coulter JB, Siddiqui I, Tran PT, Viswanathan AN, Rezaee M. FLASH Effects Induced by Orthovoltage X-Rays. Int J Radiat Oncol Biol Phys 2023; 117:1018-1027. [PMID: 37364800 DOI: 10.1016/j.ijrobp.2023.06.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 05/16/2023] [Accepted: 06/11/2023] [Indexed: 06/28/2023]
Abstract
PURPOSE This work describes the first implementation and in vivo study of ultrahigh-dose-rate radiation (>37 Gy/s; FLASH) effects induced by kilovoltage (kV) x-ray from a rotating-anode x-ray source. METHODS AND MATERIALS A high-capacity rotating-anode x-ray tube with an 80-kW generator was implemented for preclinical FLASH radiation research. A custom 3-dimensionally printed immobilization and positioning tool was developed for reproducible irradiation of a mouse hind limb. Calibrated Gafchromic (EBT3) film and thermoluminescent dosimeters (LiF:Mg,Ti) were used for in-phantom and in vivo dosimetry. Healthy FVB/N and FVBN/C57BL/6 outbred mice were irradiated on 1 hind leg to doses up to 43 Gy at FLASH (87 Gy/s) and conventional (CONV; <0.05 Gy/s) dose rates. The radiation doses were delivered using a single pulse with the widths up to 500 ms and 15 minutes at FLASH and CONV dose rates. Histologic assessment of radiation-induced skin damage was performed at 8 weeks posttreatment. Tumor growth suppression was assessed using a B16F10 flank tumor model in C57BL6J mice irradiated to 35 Gy at both FLASH and CONV dose rates. RESULTS FLASH-irradiated mice experienced milder radiation-induced skin injuries than CONV-irradiated mice, visible by 4 weeks posttreatment. At 8 weeks posttreatment, normal tissue injury was significantly reduced in FLASH-irradiated animals compared with CONV-irradiated animals for histologic endpoints including inflammation, ulceration, hyperplasia, and fibrosis. No difference in tumor growth response was observed between FLASH and CONV irradiations at 35 Gy. The normal tissue sparing effects of FLASH irradiations were observed only for high-severity endpoint of ulceration at 43 Gy, which suggests the dependency of biologic endpoints to FLASH radiation dose. CONCLUSIONS Rotating-anode x-ray sources can achieve FLASH dose rates in a single pulse with dosimetric properties suitable for small-animal experiments. We observed FLASH normal tissue sparing of radiation toxicities in mouse skin irradiated at 35 Gy with no sacrifice to tumor growth suppression. This study highlights an accessible new modality for laboratory study of the FLASH effect.
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Affiliation(s)
- Devin Miles
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Daniel Sforza
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - John W Wong
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Kathleen Gabrielson
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Khaled Aziz
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Mahadevappa Mahesh
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Jonathan B Coulter
- Department of Urology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Ismaeel Siddiqui
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Phuoc T Tran
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Akila N Viswanathan
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Mohammad Rezaee
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland.
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20
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Böhlen TT, Germond JF, Petersson K, Ozsahin EM, Herrera FG, Bailat C, Bochud F, Bourhis J, Moeckli R, Adrian G. Effect of Conventional and Ultrahigh Dose Rate FLASH Irradiations on Preclinical Tumor Models: A Systematic Analysis. Int J Radiat Oncol Biol Phys 2023; 117:1007-1017. [PMID: 37276928 DOI: 10.1016/j.ijrobp.2023.05.045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 04/19/2023] [Accepted: 05/26/2023] [Indexed: 06/07/2023]
Abstract
PURPOSE Compared with conventional dose rate irradiation (CONV), ultrahigh dose rate irradiation (UHDR) has shown superior normal tissue sparing. However, a clinically relevant widening of the therapeutic window by UHDR, termed "FLASH effect," also depends on the tumor toxicity obtained by UHDR. Based on a combined analysis of published literature, the current study examined the hypothesis of tumor isoefficacy for UHDR versus CONV and aimed to identify potential knowledge gaps to inspire future in vivo studies. METHODS AND MATERIALS A systematic literature search identified publications assessing in vivo tumor responses comparing UHDR and CONV. Qualitative and quantitative analyses were performed, including combined analyses of tumor growth and survival data. RESULTS We identified 66 data sets from 15 publications that compared UHDR and CONV for tumor efficacy. The median number of animals per group was 9 (range 3-15) and the median follow-up period was 30.5 days (range 11-230) after the first irradiation. Tumor growth assays were the predominant model used. Combined statistical analyses of tumor growth and survival data are consistent with UHDR isoefficacy compared with CONV. Only 1 study determined tumor-controlling dose (TCD50) and reported statistically nonsignificant differences. CONCLUSIONS The combined quantitative analyses of tumor responses support the assumption of UHDR isoefficacy compared with CONV. However, the comparisons are primarily based on heterogeneous tumor growth assays with limited numbers of animals and short follow-up, and most studies do not assess long-term tumor control probability. Therefore, the assays may be insensitive in resolving smaller response differences, such as responses of radioresistant tumor subclones. Hence, tumor cure experiments, including additional TCD50 experiments, are needed to confirm the assumption of isoeffectiveness in curative settings.
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Affiliation(s)
- Till Tobias Böhlen
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Jean-François Germond
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Kristoffer Petersson
- Department of Hematology, Oncology, and Radiation Physics, Skåne University Hospital, Lund, Sweden; MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, United Kingdom
| | - Esat Mahmut Ozsahin
- Department of Radiation Oncology, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Fernanda G Herrera
- Department of Radiation Oncology, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Claude Bailat
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - François Bochud
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Jean Bourhis
- Department of Radiation Oncology, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Raphaël Moeckli
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland.
| | - Gabriel Adrian
- Department of Hematology, Oncology, and Radiation Physics, Skåne University Hospital, Lund, Sweden; Division of Oncology and Pathology, Department of Clinical Sciences, Skåne University Hospital, Lund University, Lund, Sweden
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21
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Jeon C, Ahn S, Amano D, Kamiguchi N, Cho S, Sheen H, Park HC, Han Y. FLASH dose rate calculation based on log files in proton pencil beam scanning therapy. Med Phys 2023; 50:7154-7166. [PMID: 37431587 DOI: 10.1002/mp.16575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 06/05/2023] [Accepted: 06/06/2023] [Indexed: 07/12/2023] Open
Abstract
BACKGROUND In radiation therapy, irradiating healthy normal tissues in the beam trajectories is inevitable. This unnecessary dose means that patients undergoing treatment risk developing side effects. Recently, FLASH radiotherapy delivering ultra-high-dose-rate beams has been re-examined because of its normal-tissue-sparing effect. To confirm the mean and instantaneous dose rates of the FLASH beam, stable and accurate dosimetry is required. PURPOSE Detailed verification of the FLASH effect requires dosimeters and a method to measure the average and instantaneous dose rate stably for 2- or 3-dimensional dose distributions. To verify the delivered FLASH beam, we utilized machine log files from the built-in monitor chamber to develop a dosimetry method to calculate the dose and average/instantaneous dose rate distributions in two or three dimensions in a phantom. METHODS To create a spread-out Bragg peak (SOBP) and deliver a uniform dose in a target, a mini-ridge filter was created with a 3D printer. Proton pencil beam line scanning plans of 2 × 2 cm2 , 3 × 3 cm2 , 4 × 4 cm2 , and round shapes with 2.3 cm diameter patterns delivering 230 MeV energy protons were created. The absorbed dose in the solid water phantom of each plan was measured using a PPC05 ionization chamber (IBA Dosimetry, Virginia, USA) in the SOBP region, and the log files for each plan were exported from the treatment control system console. Using these log files, the delivered dose and average dose rate were calculated using two methods: a direct method and a Monte Carlo (MC) simulation method that uses log file information. The computed and average dose rates were compared with the ionization chamber measurements. Additionally, instantaneous dose rates in user-defined volumes were calculated using the MC simulation method with a temporal resolution of 5 ms. RESULTS Compared to ionization chamber dosimetry, 10 of 12 cases using the direct calculation method and 9 of 11 cases using the MC method had a dose difference below ±3%. Nine of 12 cases using the direct calculation method and 8 of 11 cases using the MC method had dose rate differences below ±3%. The average and maximum dose differences for the direct calculation and MC method were-0.17, +0.72%, and -3.15, +3.32%, respectively. For the dose rate difference, the average and maximum for the direct calculation and MC method were +1.26, +1.12%, and +3.75, +3.15%, respectively. In the instantaneous dose rate calculation with the MC simulation, a large fluctuation with a maximum of 163 Gy/s and a minimum of 4.29 Gy/s instantaneous dose rate was observed in a specific position, whereas the mean dose rate was 62 Gy/s. CONCLUSIONS We successfully developed methods in which machine log files are used to calculate the dose and the average and instantaneous dose rates for FLASH radiotherapy and demonstrated the feasibility of verifying the delivered FLASH beams.
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Affiliation(s)
- Chanil Jeon
- Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Republic of Korea
| | - Sunghwan Ahn
- Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Daizo Amano
- Sumitomo Heavy Industries, Ltd, Tokyo, Japan
| | | | - Sungkoo Cho
- Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Heesoon Sheen
- Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Hee Chul Park
- Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Youngyih Han
- Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Republic of Korea
- Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
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22
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Lin B, Fan M, Niu T, Liang Y, Xu H, Tang W, Du X. Key changes in the future clinical application of ultra-high dose rate radiotherapy. Front Oncol 2023; 13:1244488. [PMID: 37941555 PMCID: PMC10628486 DOI: 10.3389/fonc.2023.1244488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 10/09/2023] [Indexed: 11/10/2023] Open
Abstract
Ultra-high dose rate radiotherapy (FLASH-RT) is an external beam radiotherapy strategy that uses an extremely high dose rate (≥40 Gy/s). Compared with conventional dose rate radiotherapy (≤0.1 Gy/s), the main advantage of FLASH-RT is that it can reduce damage of organs at risk surrounding the cancer and retain the anti-tumor effect. An important feature of FLASH-RT is that an extremely high dose rate leads to an extremely short treatment time; therefore, in clinical applications, the steps of radiotherapy may need to be adjusted. In this review, we discuss the selection of indications, simulations, target delineation, selection of radiotherapy technologies, and treatment plan evaluation for FLASH-RT to provide a theoretical basis for future research.
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Affiliation(s)
- Binwei Lin
- Department of Oncology, National Health Commission (NHC) Key Laboratory of Nuclear Technology Medical Transformation (Mianyang Central Hospital), Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology, Mianyang, China
| | - Mi Fan
- Department of Oncology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Tingting Niu
- Department of Oncology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Yuwen Liang
- Department of Oncology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Haonan Xu
- Department of Oncology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Wenqiang Tang
- Department of Oncology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Xiaobo Du
- Department of Oncology, National Health Commission (NHC) Key Laboratory of Nuclear Technology Medical Transformation (Mianyang Central Hospital), Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology, Mianyang, China
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23
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No HJ, Wu YF, Dworkin ML, Manjappa R, Skinner L, Ashraf MR, Lau B, Melemenidis S, Viswanathan V, Yu ASJ, Surucu M, Schüler E, Graves EE, Maxim PG, Loo BW. Clinical Linear Accelerator-Based Electron FLASH: Pathway for Practical Translation to FLASH Clinical Trials. Int J Radiat Oncol Biol Phys 2023; 117:482-492. [PMID: 37105403 DOI: 10.1016/j.ijrobp.2023.04.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 03/03/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023]
Abstract
PURPOSE Ultrahigh-dose-rate (UHDR) radiation therapy (RT) has produced the FLASH effect in preclinical models: reduced toxicity with comparable tumor control compared with conventional-dose-rate RT. Early clinical trials focused on UHDR RT feasibility using specialized devices. We explore the technical feasibility of practical electron UHDR RT on a standard clinical linear accelerator (LINAC). METHODS AND MATERIALS We tuned the program board of a decommissioned electron energy for UHDR electron delivery on a clinical LINAC without hardware modification. Pulse delivery was controlled using the respiratory gating interface. A short source-to-surface distance (SSD) electron setup with a standard scattering foil was configured and tested on an anthropomorphic phantom using circular blocks with 3- to 20-cm field sizes. Dosimetry was evaluated using radiochromic film and an ion chamber profiler. RESULTS UHDR open-field mean dose rates at 100, 80, 70, and 59 cm SSD were 36.82, 59.52, 82.01, and 112.83 Gy/s, respectively. At 80 cm SSD, mean dose rate was ∼60 Gy/s for all collimated field sizes, with an R80 depth of 6.1 cm corresponding to an energy of 17.5 MeV. Heterogeneity was <5.0% with asymmetry of 2.2% to 6.2%. The short SSD setup was feasible under realistic treatment conditions simulating broad clinical indications on an anthropomorphic phantom. CONCLUSIONS Short SSD and tuning for high electron beam current on a standard clinical LINAC can deliver flat, homogenous UHDR electrons over a broad, clinically relevant range of field sizes and depths with practical working distances in a configuration easily reversible to standard clinical use.
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Affiliation(s)
- Hyunsoo Joshua No
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California
| | - Yufan Fred Wu
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California
| | - Michael Louis Dworkin
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California
| | - Rakesh Manjappa
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California
| | - Lawrie Skinner
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California
| | - M Ramish Ashraf
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California
| | - Brianna Lau
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California
| | - Stavros Melemenidis
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California
| | - Vignesh Viswanathan
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California
| | - Amy Shu-Jung Yu
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California
| | - Murat Surucu
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California
| | - Emil Schüler
- Department of Radiation Physics, Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Edward Elliot Graves
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California
| | - Peter Gregor Maxim
- Department of Radiation Oncology, University of California, Irvine, Orange, California
| | - Billy W Loo
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California.
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24
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Vanreusel V, Gasparini A, Galante F, Mariani G, Pacitti M, Colijn A, Reniers B, Yalvac B, Vandenbroucke D, Peeters M, Leblans P, Felici G, Verellen D, de Freitas Nascimento L. Optically stimulated luminescence system as an alternative for radiochromic film for 2D reference dosimetry in UHDR electron beams. Phys Med 2023; 114:103147. [PMID: 37804712 DOI: 10.1016/j.ejmp.2023.103147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 08/18/2023] [Accepted: 09/21/2023] [Indexed: 10/09/2023] Open
Abstract
Radiotherapy is part of the treatment of over 50% of cancer patients. Its efficacy is limited by the radiotoxicity to the healthy tissue. FLASH-RT is based on the biological effect that ultra-high dose rates (UHDR) and very short treatment times strongly reduce normal tissue toxicity, while preserving the anti-tumoral effect. Despite many positive preclinical results, the translation of FLASH-RT to the clinic is hampered by the lack of accurate dosimetry for UHDR beams. To date radiochromic film is commonly used for dose assessment but has the drawback of lengthy and cumbersome read out procedures. In this work, we investigate the equivalence of a 2D OSL system to radiochromic film dosimetry in terms of dose rate independency. The comparison of both systems was done using the ElectronFlash linac. We investigated the dose rate dependence by variation of the (1) modality, (2) pulse repetition frequency, (3) pulse length and (4) source to surface distance. Additionally, we compared the 2D characteristics by field size measurements. The OSL calibration showed transferable between conventional and UHDR modality. Both systems are equally independent of average dose rate, pulse length and instantaneous dose rate. The OSL system showed equivalent in field size determination within 3 sigma. We show the promising nature of the 2D OSL system to serve as alternative for radiochromic film in UHDR electron beams. However, more in depth characterization is needed to assess its full potential.
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Affiliation(s)
- Verdi Vanreusel
- Research in Dosimetric Applications, SCK CEN, Boeretang 200, 2400 Mol, Belgium; CORE, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium; Iridium Netwerk, Oosterveldlaan 22, 2610 Wilrijk, Belgium.
| | - Alessia Gasparini
- CORE, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium; Iridium Netwerk, Oosterveldlaan 22, 2610 Wilrijk, Belgium
| | - Federica Galante
- Sordina IORT Technologies S.p.A., Via dell'Industria, 1/A, 04011 Aprilia, Latina, Italy
| | - Giulia Mariani
- Sordina IORT Technologies S.p.A., Via dell'Industria, 1/A, 04011 Aprilia, Latina, Italy
| | - Matteo Pacitti
- Sordina IORT Technologies S.p.A., Via dell'Industria, 1/A, 04011 Aprilia, Latina, Italy
| | - Arnaud Colijn
- CORE, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Brigitte Reniers
- NuTeC, CMK, Hasselt University, Wetenschapspark 27, 3590 Diepenbeek, Belgium
| | - Burak Yalvac
- NuTeC, CMK, Hasselt University, Wetenschapspark 27, 3590 Diepenbeek, Belgium
| | | | | | - Paul Leblans
- Agfa N.V., Septestraat 27, 2640 Mortsel, Belgium
| | - Giuseppe Felici
- Sordina IORT Technologies S.p.A., Via dell'Industria, 1/A, 04011 Aprilia, Latina, Italy
| | - Dirk Verellen
- CORE, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium; Iridium Netwerk, Oosterveldlaan 22, 2610 Wilrijk, Belgium
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Jo HJ, Oh T, Lee YR, Kang GS, Park HJ, Ahn GO. FLASH Radiotherapy: A FLASHing Idea to Preserve Neurocognitive Function. Brain Tumor Res Treat 2023; 11:223-231. [PMID: 37953445 PMCID: PMC10641319 DOI: 10.14791/btrt.2023.0026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/17/2023] [Accepted: 09/11/2023] [Indexed: 11/14/2023] Open
Abstract
FLASH radiotherapy (FLASH RT) is a technique to deliver ultra-high dose rate in a fraction of a second. Evidence from experimental animal models suggest that FLASH RT spares various normal tissues including the lung, gastrointestinal track, and brain from radiation-induced toxicity (a phenomenon known as FLASH effect), which is otherwise commonly observed with conventional dose rate RT. However, it is not simply the ultra-high dose rate alone that brings the FLASH effect. Multiple parameters such as instantaneous dose rate, pulse size, pulse repetition frequency, and the total duration of exposure all need to be carefully optimized simultaneously. Furthermore it is critical to validate FLASH effects in an in vivo experimental model system. The exact molecular mechanism responsible for this FLASH effect is not yet understood although a number of hypotheses have been proposed including oxygen depletion and less reactive oxygen species (ROS) production by FLASH RT, and enhanced ability of normal tissues to handle ROS and labile iron pool compared to tumors. In this review, we briefly overview the process of ionization event and history of radiotherapy and fractionation of ionizing radiation. We also highlight some of the latest FLASH RT reviews and results with a special interest to neurocognitive protection in rodent model with whole brain irradiation. Lastly we discuss some of the issues remain to be answered with FLASH RT including undefined molecular mechanism, lack of standardized parameters, low penetration depth for electron beam, and tumor hypoxia still being a major hurdle for local control. Nevertheless, researchers are close to having all answers to the issues that we have raised, hence we believe that advancement of FLASH RT will be made more quickly than one can anticipate.
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Affiliation(s)
- Hye-Ju Jo
- College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - Taerim Oh
- College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - Ye-Rim Lee
- College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - Gi-Sue Kang
- College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - Hye-Joon Park
- College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - G-One Ahn
- College of Veterinary Medicine, Seoul National University, Seoul, Korea
- College of Medicine, Seoul National University, Seoul, Korea.
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Børresen B, Arendt ML, Konradsson E, Bastholm Jensen K, Bäck SÅJ, Munck af Rosenschöld P, Ceberg C, Petersson K. Evaluation of single-fraction high dose FLASH radiotherapy in a cohort of canine oral cancer patients. Front Oncol 2023; 13:1256760. [PMID: 37766866 PMCID: PMC10520273 DOI: 10.3389/fonc.2023.1256760] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 08/24/2023] [Indexed: 09/29/2023] Open
Abstract
Background FLASH radiotherapy (RT) is a novel method for delivering ionizing radiation, which has been shown in preclinical studies to have a normal tissue sparing effect and to maintain anticancer efficacy as compared to conventional RT. Treatment of head and neck tumors with conventional RT is commonly associated with severe toxicity, hence the normal tissue sparing effect of FLASH RT potentially makes it especially advantageous for treating oral tumors. In this work, the objective was to study the adverse effects of dogs with spontaneous oral tumors treated with FLASH RT. Methods Privately-owned dogs with macroscopic malignant tumors of the oral cavity were treated with a single fraction of ≥30Gy electron FLASH RT and subsequently followed for 12 months. A modified conventional linear accelerator was used to deliver the FLASH RT. Results Eleven dogs were enrolled in this prospective study. High grade adverse effects were common, especially if bone was included in the treatment field. Four out of six dogs, who had bone in their treatment field and lived at least 5 months after RT, developed osteoradionecrosis at 3-12 months post treatment. The treatment was overall effective with 8/11 complete clinical responses and 3/11 partial responses. Conclusion This study shows that single-fraction high dose FLASH RT was generally effective in this mixed group of malignant oral tumors, but the risk of osteoradionecrosis is a serious clinical concern. It is possible that the risk of osteonecrosis can be mitigated through fractionation and improved dose conformity, which needs to be addressed before moving forward with clinical trials in human cancer patients.
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Affiliation(s)
- Betina Børresen
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Maja L. Arendt
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Elise Konradsson
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | | | - Sven ÅJ. Bäck
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Per Munck af Rosenschöld
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Crister Ceberg
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Kristoffer Petersson
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
- Department of Oncology, Oxford Institute for Radiation Oncology, University of Oxford, Oxford, United Kingdom
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Kawahara D, Nagata Y. Biological dosimetric impact of dose-delivery time for hypoxic tumour with modified microdosimetric kinetic model. Rep Pract Oncol Radiother 2023; 28:514-521. [PMID: 37795224 PMCID: PMC10547428 DOI: 10.5603/rpor.a2023.0062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 08/03/2023] [Indexed: 10/06/2023] Open
Abstract
Background An improved microdosimetric kinetic model (MKM) can address radiobiological effects with prolonged delivery times. However, these do not consider the effects of oxygen. The current study aimed to evaluate the biological dosimetric effects associated with the dose delivery time in hypoxic tumours with improved MKM for photon radiation therapy. Materials and methods Cell survival was measured under anoxic, hypoxic, and oxic conditions using the Monte Carlo code PHITS. The effect of the dose rate of 0.5-24 Gy/min for the biological dose (Dbio) was estimated using the microdosimetric kinetic model. The dose per fraction and pressure of O2 (pO2) in the tumour varied from 2 to 20 Gy and from 0.01 to 5.0% pO2, respectively. Results The ratio of the Dbio at 1.0-24 Gy/min to that at 0.5 Gy/min (RDR) was higher at higher doses. The maximum RDR was 1.09 at 1.0 Gy/min, 1.12 at 12 Gy/min, and 1.13 at 24 Gy/min. The ratio of the Dbio at 0.01-2.0% of pO2 to that at 5.0% of pO2 (Roxy) was within 0.1 for 2-20 Gy of physical dose. The maximum Roxy was 0.42 at 0.01% pO2, 0.76 at 0.4% pO2, 0.89 at 1% pO2, and 0.96 at 2% pO2. Conclusion Our proposed model can estimate the cell killing and biological dose under hypoxia in a clinical and realistic patient. A shorter dose-delivery time with a higher oxygen distribution increased the radiobiological effect. It was more effective at higher doses per fraction than at lower doses.
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Affiliation(s)
- Daisuke Kawahara
- Department of Radiation Oncology, Institute of Biomedical & Health Science, Hiroshima University, Japan
| | - Yasushi Nagata
- Department of Radiation Oncology, Institute of Biomedical & Health Science, Hiroshima University, Japan
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Zou W, Zhang R, Schüler E, Taylor PA, Mascia AE, Diffenderfer ES, Zhao T, Ayan AS, Sharma M, Yu SJ, Lu W, Bosch WR, Tsien C, Surucu M, Pollard-Larkin JM, Schuemann J, Moros EG, Bazalova-Carter M, Gladstone DJ, Li H, Simone CB, Petersson K, Kry SF, Maity A, Loo BW, Dong L, Maxim PG, Xiao Y, Buchsbaum JC. Framework for Quality Assurance of Ultrahigh Dose Rate Clinical Trials Investigating FLASH Effects and Current Technology Gaps. Int J Radiat Oncol Biol Phys 2023; 116:1202-1217. [PMID: 37121362 PMCID: PMC10526970 DOI: 10.1016/j.ijrobp.2023.04.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 03/28/2023] [Accepted: 04/17/2023] [Indexed: 05/02/2023]
Abstract
FLASH radiation therapy (FLASH-RT), delivered with ultrahigh dose rate (UHDR), may allow patients to be treated with less normal tissue toxicity for a given tumor dose compared with currently used conventional dose rate. Clinical trials are being carried out and are needed to test whether this improved therapeutic ratio can be achieved clinically. During the clinical trials, quality assurance and credentialing of equipment and participating sites, particularly pertaining to UHDR-specific aspects, will be crucial for the validity of the outcomes of such trials. This report represents an initial framework proposed by the NRG Oncology Center for Innovation in Radiation Oncology FLASH working group on quality assurance of potential UHDR clinical trials and reviews current technology gaps to overcome. An important but separate consideration is the appropriate design of trials to most effectively answer clinical and scientific questions about FLASH. This paper begins with an overview of UHDR RT delivery methods. UHDR beam delivery parameters are then covered, with a focus on electron and proton modalities. The definition and control of safe UHDR beam delivery and current and needed dosimetry technologies are reviewed and discussed. System and site credentialing for large, multi-institution trials are reviewed. Quality assurance is then discussed, and new requirements are presented for treatment system standard analysis, patient positioning, and treatment planning. The tables and figures in this paper are meant to serve as reference points as we move toward FLASH-RT clinical trial performance. Some major questions regarding FLASH-RT are discussed, and next steps in this field are proposed. FLASH-RT has potential but is associated with significant risks and complexities. We need to redefine optimization to focus not only on the dose but also on the dose rate in a manner that is robust and understandable and that can be prescribed, validated, and confirmed in real time. Robust patient safety systems and access to treatment data will be critical as FLASH-RT moves into the clinical trials.
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Affiliation(s)
- Wei Zou
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA.
| | - Rongxiao Zhang
- Department of Radiation Oncology, Geisel School of Medicine, Dartmouth College, Hanover, NH, USA
| | - Emil Schüler
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Paige A Taylor
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | | | - Eric S Diffenderfer
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA
| | - Tianyu Zhao
- Department of Radiation Oncology, Washington University, St. Louis, MO, USA
| | - Ahmet S Ayan
- Department of Radiation Oncology, Ohio State University, Columbus, OH, USA
| | - Manju Sharma
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, USA
| | - Shu-Jung Yu
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Weiguo Lu
- Department of Radiation Oncology, University of Texas Southwestern, Dallas, TX, USA
| | - Walter R Bosch
- Department of Radiation Oncology, Washington University, St. Louis, MO, USA
| | - Christina Tsien
- Department of Radiation Oncology, McGill University Health Center, Montreal, QC, Canada
| | - Murat Surucu
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Julianne M Pollard-Larkin
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jan Schuemann
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Eduardo G Moros
- Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL, USA
| | | | - David J Gladstone
- Department of Radiation Oncology, Geisel School of Medicine, Dartmouth College, Hanover, NH, USA
| | - Heng Li
- Department of Radiation Oncology, Johns Hopkins University, Baltimore, MD, USA
| | - Charles B Simone
- Department of Radiation Oncology, New York Proton Center, New York, NY, USA
| | - Kristoffer Petersson
- Department of Radiation Oncology, MRC Oxford Institute for Radiation Oncology, University of Oxford, Oxford, UK
| | - Stephen F Kry
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Amit Maity
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA
| | - Billy W Loo
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Lei Dong
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA
| | - Peter G Maxim
- Department of Radiation Oncology, University of California Irvine, Irvine, CA, USA
| | - Ying Xiao
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA
| | - Jeffrey C Buchsbaum
- Radiation Research Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute, National Institute of Health, Bethesda, MD, USA
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Cuitiño MC, Fleming JL, Jain S, Cetnar A, Ayan AS, Woollard J, Manring H, Meng W, McElroy JP, Blakaj DM, Gupta N, Chakravarti A. Comparison of Gonadal Toxicity of Single-Fraction Ultra-High Dose Rate and Conventional Radiation in Mice. Adv Radiat Oncol 2023; 8:101201. [PMID: 37008254 PMCID: PMC10050676 DOI: 10.1016/j.adro.2023.101201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 02/08/2023] [Indexed: 02/25/2023] Open
Abstract
Purpose Increasing evidence suggests that ultra-high-dose-rate (UHDR) radiation could result in similar tumor control as conventional (CONV) radiation therapy (RT) while reducing toxicity to surrounding healthy tissues. Considering that radiation toxicity to gonadal tissues can cause hormone disturbances and infertility in young patients with cancer, the purpose of this study was to assess the possible role of UHDR-RT in reducing toxicity to healthy gonads in mice compared with CONV-RT. Methods and Materials Radiation was delivered to the abdomen or pelvis of female (8 or 16 Gy) and male (5 Gy) C57BL/6J mice, respectively, at conventional (∼0.4 Gy/s) or ultrahigh (>100 Gy/s) dose rates using an IntraOp Mobetron linear accelerator. Organ weights along with histopathology and immunostaining of irradiated gonads were used to compare toxicity between radiation modalities. Results CONV-RT and UHDR-RT induced a similar decrease in uterine weights at both studied doses (∼50% of controls), which indicated similarly reduced ovarian follicular activity. Histologically, ovaries of CONV- and UHDR-irradiated mice exhibited a comparable lack of follicles. Weights of CONV- and UHDR-irradiated testes were reduced to ∼30% of controls, and the percentage of degenerate seminiferous tubules was also similar between radiation modalities (∼80% above controls). Pairwise comparisons of all quantitative data indicated statistical significance between irradiated (CONV or UHDR) and control groups (from P ≤ .01 to P ≤ .0001) but not between radiation modalities. Conclusions The data presented here suggest that the short-term effects of UHDR-RT on the mouse gonads are comparable to those of CONV-RT.
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Affiliation(s)
- Maria C. Cuitiño
- Department of Radiation Oncology, Arthur G. James Hospital, Comprehensive Cancer Center, Columbus, Ohio
| | - Jessica L. Fleming
- Department of Radiation Oncology, Arthur G. James Hospital, Comprehensive Cancer Center, Columbus, Ohio
| | - Sagarika Jain
- Department of Radiation Oncology, Arthur G. James Hospital, Comprehensive Cancer Center, Columbus, Ohio
| | - Ashley Cetnar
- Department of Radiation Oncology, Arthur G. James Hospital, Comprehensive Cancer Center, Columbus, Ohio
| | - Ahmet S. Ayan
- Department of Radiation Oncology, Arthur G. James Hospital, Comprehensive Cancer Center, Columbus, Ohio
| | - Jeffrey Woollard
- Department of Radiation Oncology, Arthur G. James Hospital, Comprehensive Cancer Center, Columbus, Ohio
| | - Heather Manring
- Department of Radiation Oncology, Arthur G. James Hospital, Comprehensive Cancer Center, Columbus, Ohio
| | - Wei Meng
- Department of Radiation Oncology, Arthur G. James Hospital, Comprehensive Cancer Center, Columbus, Ohio
| | - Joseph P. McElroy
- Department of Biomedical Informatics, Center for Biostatistics, Ohio State University, Columbus, Ohio
| | - Dukagjin M. Blakaj
- Department of Radiation Oncology, Arthur G. James Hospital, Comprehensive Cancer Center, Columbus, Ohio
| | - Nilendu Gupta
- Department of Radiation Oncology, Arthur G. James Hospital, Comprehensive Cancer Center, Columbus, Ohio
| | - Arnab Chakravarti
- Department of Radiation Oncology, Arthur G. James Hospital, Comprehensive Cancer Center, Columbus, Ohio
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Vanhaezebrouck IF, Scarpelli ML. Companion Animals as a Key to Success for Translating Radiation Therapy Research into the Clinic. Cancers (Basel) 2023; 15:3377. [PMID: 37444487 PMCID: PMC10341092 DOI: 10.3390/cancers15133377] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 06/23/2023] [Accepted: 06/23/2023] [Indexed: 07/15/2023] Open
Abstract
Many successful preclinical findings fail to be replicated during translation to human studies. This leads to significant resources being spent on large clinical trials, and in some cases, promising therapeutics not being pursued due to the high costs of clinical translation. These translational failures emphasize the need for improved preclinical models of human cancer so that there is a higher probability of successful clinical translation. Companion-animal cancers offer a potential solution. These cancers are more similar to human cancer than other preclinical models, with a natural evolution over time, genetic alterations, intact immune system, and a permanent adaptation to the microenvironment. These advantages have led pioneers in veterinary radiation oncology to aid human medicine by elucidating basic principles of radiation biology. More recently, the veterinary and human radiation oncology fields have increasingly collaborated to achieve advancements in education, radiotherapy techniques, and trial networks. This review describes these advancements, including significant prior research findings and the evolution of the veterinary radiation oncology discipline. It concludes by describing how companion-animal models can help shape the future of human radiotherapy. Taken as a whole, this review suggests companion-animal cancers may become widely used for preclinical radiotherapy research.
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Affiliation(s)
| | - Matthew L. Scarpelli
- School of Health Sciences, Purdue University, 550 W Stadium Ave, West Lafayette, IN 47907, USA;
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Atkinson J, Bezak E, Le H, Kempson I. The current status of FLASH particle therapy: a systematic review. Phys Eng Sci Med 2023; 46:529-560. [PMID: 37160539 DOI: 10.1007/s13246-023-01266-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Accepted: 04/20/2023] [Indexed: 05/11/2023]
Abstract
Particle therapies are becoming increasingly available clinically due to their beneficial energy deposition profile, sparing healthy tissues. This may be further promoted with ultra-high dose rates, termed FLASH. This review comprehensively summarises current knowledge based on studies relevant to proton- and carbon-FLASH therapy. As electron-FLASH literature presents important radiobiological findings that form the basis of proton and carbon-based FLASH studies, a summary of key electron-FLASH papers is also included. Preclinical data suggest three key mechanisms by which proton and carbon-FLASH are able to reduce normal tissue toxicities compared to conventional dose rates, with equipotent, or enhanced, tumour kill efficacy. However, a degree of caution is needed in clinically translating these findings as: most studies use transmission and do not conform the Bragg peak to tumour volume; mechanistic understanding is still in its infancy; stringent verification of dosimetry is rarely provided; biological assays are prone to limitations which need greater acknowledgement.
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Affiliation(s)
- Jake Atkinson
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, 5095, Australia
| | - Eva Bezak
- Cancer Research Institute, University of South Australia, Adelaide, South Australia, 5000, Australia
- Department of Physics, University of Adelaide, North Terrace, Adelaide, South Australia, 5000, Australia
| | - Hien Le
- Department of Radiation Oncology, Royal Adelaide Hospital, Adelaide, 5000, Australia
| | - Ivan Kempson
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, 5095, Australia.
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Allen BD, Alaghband Y, Kramár EA, Ru N, Petit B, Grilj V, Petronek MS, Pulliam CF, Kim RY, Doan NL, Baulch JE, Wood MA, Bailat C, Spitz DR, Vozenin MC, Limoli CL. Elucidating the neurological mechanism of the FLASH effect in juvenile mice exposed to hypofractionated radiotherapy. Neuro Oncol 2023; 25:927-939. [PMID: 36334265 PMCID: PMC10158064 DOI: 10.1093/neuonc/noac248] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND Ultrahigh dose-rate radiotherapy (FLASH-RT) affords improvements in the therapeutic index by minimizing normal tissue toxicities without compromising antitumor efficacy compared to conventional dose-rate radiotherapy (CONV-RT). To investigate the translational potential of FLASH-RT to a human pediatric medulloblastoma brain tumor, we used a radiosensitive juvenile mouse model to assess adverse long-term neurological outcomes. METHODS Cohorts of 3-week-old male and female C57Bl/6 mice exposed to hypofractionated (2 × 10 Gy, FLASH-RT or CONV-RT) whole brain irradiation and unirradiated controls underwent behavioral testing to ascertain cognitive status four months posttreatment. Animals were sacrificed 6 months post-irradiation and tissues were analyzed for neurological and cerebrovascular decrements. RESULTS The neurological impact of FLASH-RT was analyzed over a 6-month follow-up. FLASH-RT ameliorated neurocognitive decrements induced by CONV-RT and preserved synaptic plasticity and integrity at the electrophysiological (long-term potentiation), molecular (synaptophysin), and structural (Bassoon/Homer-1 bouton) levels in multiple brain regions. The benefits of FLASH-RT were also linked to reduced neuroinflammation (activated microglia) and the preservation of the cerebrovascular structure, by maintaining aquaporin-4 levels and minimizing microglia colocalized to vessels. CONCLUSIONS Hypofractionated FLASH-RT affords significant and long-term normal tissue protection in the radiosensitive juvenile mouse brain when compared to CONV-RT. The capability of FLASH-RT to preserve critical cognitive outcomes and electrophysiological properties over 6-months is noteworthy and highlights its potential for resolving long-standing complications faced by pediatric brain tumor survivors. While care must be exercised before clinical translation is realized, present findings document the marked benefits of FLASH-RT that extend from synapse to cognition and the microvasculature.
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Affiliation(s)
- Barrett D Allen
- Department of Radiation Oncology, University of California, Irvine, CA 92697-2695, USA
| | - Yasaman Alaghband
- Department of Radiation Oncology, University of California, Irvine, CA 92697-2695, USA
| | - Eniko A Kramár
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
| | - Ning Ru
- Department of Radiation Oncology, University of California, Irvine, CA 92697-2695, USA
| | - Benoit Petit
- Laboratory of Radiation Oncology, Department of Radiation Oncology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Veljko Grilj
- Laboratory of Radiation Oncology, Department of Radiation Oncology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Michael S Petronek
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA
| | - Casey F Pulliam
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA
| | - Rachel Y Kim
- Department of Radiation Oncology, University of California, Irvine, CA 92697-2695, USA
| | - Ngoc-Lien Doan
- Department of Radiation Oncology, University of California, Irvine, CA 92697-2695, USA
| | - Janet E Baulch
- Department of Radiation Oncology, University of California, Irvine, CA 92697-2695, USA
| | - Marcelo A Wood
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
| | - Claude Bailat
- Institute of Radiation Physics/CHUV, Lausanne University Hospital, Lausanne, Switzerland
| | - Douglas R Spitz
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA
| | - Marie-Catherine Vozenin
- Laboratory of Radiation Oncology, Department of Radiation Oncology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Charles L Limoli
- Department of Radiation Oncology, University of California, Irvine, CA 92697-2695, USA
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van Marlen P, van de Water S, Dahele M, Slotman BJ, Verbakel WFAR. Single Ultra-High Dose Rate Proton Transmission Beam for Whole Breast FLASH-Irradiation: Quantification of FLASH-Dose and Relation with Beam Parameters. Cancers (Basel) 2023; 15:cancers15092579. [PMID: 37174045 PMCID: PMC10177419 DOI: 10.3390/cancers15092579] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 04/25/2023] [Accepted: 04/27/2023] [Indexed: 05/15/2023] Open
Abstract
Healthy tissue-sparing effects of FLASH (≥40 Gy/s, ≥4-8 Gy/fraction) radiotherapy (RT) make it potentially useful for whole breast irradiation (WBI), since there is often a lot of normal tissue within the planning target volume (PTV). We investigated WBI plan quality and determined FLASH-dose for various machine settings using ultra-high dose rate (UHDR) proton transmission beams (TBs). While five-fraction WBI is commonplace, a potential FLASH-effect might facilitate shorter treatments, so hypothetical 2- and 1-fraction schedules were also analyzed. Using one tangential 250 MeV TB delivering 5 × 5.7 Gy, 2 × 9.74 Gy or 1 × 14.32 Gy, we evaluated: (1) spots with equal monitor units (MUs) in a uniform square grid with variable spacing; (2) spot MUs optimized with a minimum MU-threshold; and (3) splitting the optimized TB into two sub-beams: one delivering spots above an MU-threshold, i.e., at UHDRs; the other delivering the remaining spots necessary to improve plan quality. Scenarios 1-3 were planned for a test case, and scenario 3 was also planned for three other patients. Dose rates were calculated using the pencil beam scanning dose rate and the sliding-window dose rate. Various machine parameters were considered: minimum spot irradiation time (minST): 2 ms/1 ms/0.5 ms; maximum nozzle current (maxN): 200 nA/400 nA/800 nA; two gantry-current (GC) techniques: energy-layer and spot-based. For the test case (PTV = 819 cc) we found: (1) a 7 mm grid achieved the best balance between plan quality and FLASH-dose for equal-MU spots; (2) near the target boundary, lower-MU spots are necessary for homogeneity but decrease FLASH-dose; (3) the non-split beam achieved >95% FLASH for favorable (not clinically available) machine parameters (SB GC, low minST, high maxN), but <5% for clinically available settings (EB GC, minST = 2 ms, maxN = 200 nA); and (4) splitting gave better plan quality and higher FLASH-dose (~50%) for available settings. The clinical cases achieved ~50% (PTV = 1047 cc) or >95% (PTV = 477/677 cc) FLASH after splitting. A single UHDR-TB for WBI can achieve acceptable plan quality. Current machine parameters limit FLASH-dose, which can be partially overcome using beam-splitting. WBI FLASH-RT is technically feasible.
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Affiliation(s)
- Patricia van Marlen
- Department of Radiation Oncology, Amsterdam UMC, Vrije Universiteit Amsterdam, Cancer Center Amsterdam, De Boelelaan 1117, 1118, 1081 HV Amsterdam, The Netherlands
| | - Steven van de Water
- Department of Radiation Oncology, Amsterdam UMC, Vrije Universiteit Amsterdam, Cancer Center Amsterdam, De Boelelaan 1117, 1118, 1081 HV Amsterdam, The Netherlands
| | - Max Dahele
- Department of Radiation Oncology, Amsterdam UMC, Vrije Universiteit Amsterdam, Cancer Center Amsterdam, De Boelelaan 1117, 1118, 1081 HV Amsterdam, The Netherlands
| | - Berend J Slotman
- Department of Radiation Oncology, Amsterdam UMC, Vrije Universiteit Amsterdam, Cancer Center Amsterdam, De Boelelaan 1117, 1118, 1081 HV Amsterdam, The Netherlands
| | - Wilko F A R Verbakel
- Department of Radiation Oncology, Amsterdam UMC, Vrije Universiteit Amsterdam, Cancer Center Amsterdam, De Boelelaan 1117, 1118, 1081 HV Amsterdam, The Netherlands
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Gaito S, Marvaso G, Ortiz R, Crellin A, Aznar MC, Indelicato DJ, Pan S, Whitfield G, Alongi F, Jereczek-Fossa BA, Burnet N, Li MP, Rothwell B, Smith E, Colaco RJ. Proton Beam Therapy in the Oligometastatic/Oligorecurrent Setting: Is There a Role? A Literature Review. Cancers (Basel) 2023; 15:cancers15092489. [PMID: 37173955 PMCID: PMC10177340 DOI: 10.3390/cancers15092489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/21/2023] [Accepted: 04/25/2023] [Indexed: 05/15/2023] Open
Abstract
BACKGROUND Stereotactic ablative radiotherapy (SABR) and stereotactic radiosurgery (SRS) with conventional photon radiotherapy (XRT) are well-established treatment options for selected patients with oligometastatic/oligorecurrent disease. The use of PBT for SABR-SRS is attractive given the property of a lack of exit dose. The aim of this review is to evaluate the role and current utilisation of PBT in the oligometastatic/oligorecurrent setting. METHODS Using Medline and Embase, a comprehensive literature review was conducted following the PICO (Patients, Intervention, Comparison, and Outcomes) criteria, which returned 83 records. After screening, 16 records were deemed to be relevant and included in the review. RESULTS Six of the sixteen records analysed originated in Japan, six in the USA, and four in Europe. The focus was oligometastatic disease in 12, oligorecurrence in 3, and both in 1. Most of the studies analysed (12/16) were retrospective cohorts or case reports, two were phase II clinical trials, one was a literature review, and one study discussed the pros and cons of PBT in these settings. The studies presented in this review included a total of 925 patients. The metastatic sites analysed in these articles were the liver (4/16), lungs (3/16), thoracic lymph nodes (2/16), bone (2/16), brain (1/16), pelvis (1/16), and various sites in 2/16. CONCLUSIONS PBT could represent an option for the treatment of oligometastatic/oligorecurrent disease in patients with a low metastatic burden. Nevertheless, due to its limited availability, PBT has traditionally been funded for selected tumour indications that are defined as curable. The availability of new systemic therapies has widened this definition. This, together with the exponential growth of PBT capacity worldwide, will potentially redefine its commissioning to include selected patients with oligometastatic/oligorecurrent disease. To date, PBT has been used with encouraging results for the treatment of liver metastases. However, PBT could be an option in those cases in which the reduced radiation exposure to normal tissues leads to a clinically significant reduction in treatment-related toxicities.
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Affiliation(s)
- Simona Gaito
- Proton Clinical Outcomes Unit, The Christie NHS Proton Beam Therapy Centre, Manchester M20 4BX, UK
- Division of Clinical Cancer Science, School of Medical Sciences, The University of Manchester, Manchester M13 9PL, UK
| | - Giulia Marvaso
- Department of Oncology and Hemato-Oncology, University of Milan, 20122 Milan, Italy
- Department of Radiation Oncology, IEO European Institute of Oncology IRCCS, 20126 Milan, Italy
| | - Ramon Ortiz
- Department of Radiation Oncology, University of California, San Francisco, CA 94720, USA
| | - Adrian Crellin
- National Lead Proton Beam Therapy NHSe, Manchester M20 4BX, UK
| | - Marianne C Aznar
- Division of Clinical Cancer Science, School of Medical Sciences, The University of Manchester, Manchester M13 9PL, UK
| | - Daniel J Indelicato
- Department of Radiation Oncology, University of Florida, Jacksonville, FL 32206, USA
| | - Shermaine Pan
- Department of Proton Beam Therapy, The Christie Proton Beam Therapy Centre, Manchester M20 3DA, UK
| | - Gillian Whitfield
- Division of Clinical Cancer Science, School of Medical Sciences, The University of Manchester, Manchester M13 9PL, UK
- Department of Proton Beam Therapy, The Christie Proton Beam Therapy Centre, Manchester M20 3DA, UK
| | - Filippo Alongi
- Advanced Radiation Oncology Department, IRCCS Ospedale Sacro Cuore don Calabria, 37024 Verona, Italy
- Division of Radiology and Radiotherapy, University of Brescia, 25121 Brescia, Italy
| | - Barbara Alicja Jereczek-Fossa
- Department of Oncology and Hemato-Oncology, University of Milan, 20122 Milan, Italy
- Department of Radiation Oncology, IEO European Institute of Oncology IRCCS, 20126 Milan, Italy
| | - Neil Burnet
- Department of Proton Beam Therapy, The Christie Proton Beam Therapy Centre, Manchester M20 3DA, UK
| | - Michelle P Li
- Department of Proton Beam Therapy, The Christie Proton Beam Therapy Centre, Manchester M20 3DA, UK
- Department of Radiation Oncology, Peter MacCallum Cancer Centre, Melbourne, VIC 3000, Australia
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Bethany Rothwell
- Division of Physics, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Ed Smith
- Proton Clinical Outcomes Unit, The Christie NHS Proton Beam Therapy Centre, Manchester M20 4BX, UK
- Division of Clinical Cancer Science, School of Medical Sciences, The University of Manchester, Manchester M13 9PL, UK
- Department of Proton Beam Therapy, The Christie Proton Beam Therapy Centre, Manchester M20 3DA, UK
| | - Rovel J Colaco
- Department of Proton Beam Therapy, The Christie Proton Beam Therapy Centre, Manchester M20 3DA, UK
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Almeida A, Togno M, Ballesteros-Zebadua P, Franco-Perez J, Geyer R, Schaefer R, Petit B, Grilj V, Meer D, Safai S, Lomax T, Weber DC, Bailat C, Psoroulas S, Vozenin MC. Dosimetric and biologic intercomparison between electron and proton FLASH beams. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.20.537497. [PMID: 37131769 PMCID: PMC10153243 DOI: 10.1101/2023.04.20.537497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Background and purpose The FLASH effect has been validated in different preclinical experiments with electrons (eFLASH) and protons (pFLASH) operating at a mean dose rate above 40 Gy/s. However, no systematic intercomparison of the FLASH effect produced by e vs. pFLASH has yet been performed and constitutes the aim of the present study. Materials and methods The electron eRT6/Oriatron/CHUV/5.5 MeV and proton Gantry1/PSI/170 MeV were used to deliver conventional (0.1 Gy/s eCONV and pCONV) and FLASH (≥100 Gy/s eFLASH and pFLASH) irradiation. Protons were delivered in transmission. Dosimetric and biologic intercomparisons were performed with previously validated models. Results Doses measured at Gantry1 were in agreement (± 2.5%) with reference dosimeters calibrated at CHUV/IRA. The neurocognitive capacity of e and pFLASH irradiated mice was indistinguishable from the control while both e and pCONV irradiated cohorts showed cognitive decrements. Complete tumor response was obtained with the two beams and was similar between e and pFLASH vs. e and pCONV. Tumor rejection was similar indicating that T-cell memory response is beam-type and dose-rate independent. Conclusion Despite major differences in the temporal microstructure, this study shows that dosimetric standards can be established. The sparing of brain function and tumor control produced by the two beams were similar, suggesting that the most important physical parameter driving the FLASH effect is the overall time of exposure which should be in the range of hundreds of milliseconds for WBI in mice. In addition, we observed that immunological memory response is similar between electron and proton beams and is independent off the dose rate.
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Affiliation(s)
- A Almeida
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - M Togno
- Center for Proton Therapy, Paul Scherrer Institute, 5323 Villigen PSI, Switzerland
| | - P Ballesteros-Zebadua
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
- Instituto Nacional de Neurología y Neurocirugía MVS, Mexico City, Mexico
| | - J Franco-Perez
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
- Instituto Nacional de Neurología y Neurocirugía MVS, Mexico City, Mexico
| | - R Geyer
- Department of Radiation Oncology, lnselspital, Bern University Hospital, University of Bern, Switzerland
| | - R Schaefer
- Center for Proton Therapy, Paul Scherrer Institute, 5323 Villigen PSI, Switzerland
| | - B Petit
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - V Grilj
- Institute of Radiation Physics (IRA)/CHUV, Lausanne University Hospital, Lausanne, Switzerland
| | - D Meer
- Center for Proton Therapy, Paul Scherrer Institute, 5323 Villigen PSI, Switzerland
| | - S Safai
- Center for Proton Therapy, Paul Scherrer Institute, 5323 Villigen PSI, Switzerland
| | - T Lomax
- Center for Proton Therapy, Paul Scherrer Institute, 5323 Villigen PSI, Switzerland
| | - D C Weber
- Center for Proton Therapy, Paul Scherrer Institute, 5323 Villigen PSI, Switzerland
- Department of Radiation Oncology, lnselspital, Bern University Hospital, University of Bern, Switzerland
- Department of Radiation Oncology, University Hospital of Zurich, Switzerland
| | - C Bailat
- Institute of Radiation Physics (IRA)/CHUV, Lausanne University Hospital, Lausanne, Switzerland
| | - S Psoroulas
- Center for Proton Therapy, Paul Scherrer Institute, 5323 Villigen PSI, Switzerland
| | - M C Vozenin
- Laboratory of Radiation Oncology/Radiation Oncology Service/Department of Oncology/CHUV, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
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Zhang Q, Gerweck LE, Cascio E, Gu L, Yang Q, Dong X, Huang P, Bertolet A, Nesteruk KP, Sung W, McNamara AL, Schuemann J. Absence of Tissue-Sparing Effects in Partial Proton FLASH Irradiation in Murine Intestine. Cancers (Basel) 2023; 15:cancers15082269. [PMID: 37190197 DOI: 10.3390/cancers15082269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 04/07/2023] [Accepted: 04/11/2023] [Indexed: 05/17/2023] Open
Abstract
Ultra-high dose rate irradiation has been reported to protect normal tissues more than conventional dose rate irradiation. This tissue sparing has been termed the FLASH effect. We investigated the FLASH effect of proton irradiation on the intestine as well as the hypothesis that lymphocyte depletion is a cause of the FLASH effect. A 16 × 12 mm2 elliptical field with a dose rate of ~120 Gy/s was provided by a 228 MeV proton pencil beam. Partial abdominal irradiation was delivered to C57BL/6j and immunodeficient Rag1-/-/C57 mice. Proliferating crypt cells were counted at 2 days post exposure, and the thickness of the muscularis externa was measured at 280 days following irradiation. FLASH irradiation did not reduce the morbidity or mortality of conventional irradiation in either strain of mice; in fact, a tendency for worse survival in FLASH-irradiated mice was observed. There were no significant differences in lymphocyte numbers between FLASH and conventional-dose-rate mice. A similar number of proliferating crypt cells and a similar thickness of the muscularis externa following FLASH and conventional dose rate irradiation were observed. Partial abdominal FLASH proton irradiation at 120 Gy/s did not spare normal intestinal tissue, and no difference in lymphocyte depletion was observed. This study suggests that the effect of FLASH irradiation may depend on multiple factors, and in some cases dose rates of over 100 Gy/s do not induce a FLASH effect and can even result in worse outcomes.
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Affiliation(s)
- Qixian Zhang
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02129, USA
| | - Leo E Gerweck
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02129, USA
| | - Ethan Cascio
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02129, USA
| | - Liqun Gu
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02129, USA
| | - Qingyuan Yang
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02129, USA
| | - Xinyue Dong
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02129, USA
| | - Peigen Huang
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02129, USA
| | - Alejandro Bertolet
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02129, USA
| | - Konrad Pawel Nesteruk
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02129, USA
| | - Wonmo Sung
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02129, USA
| | - Aimee L McNamara
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02129, USA
| | - Jan Schuemann
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA 02129, USA
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Cooper CR, Jones DJL, Jones GDD, Petersson K. Comet Assay Profiling of FLASH-Induced Damage: Mechanistic Insights into the Effects of FLASH Irradiation. Int J Mol Sci 2023; 24:7195. [PMID: 37108360 PMCID: PMC10138874 DOI: 10.3390/ijms24087195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 04/06/2023] [Accepted: 04/10/2023] [Indexed: 04/29/2023] Open
Abstract
Numerous studies have demonstrated the normal tissue-sparing effects of ultra-high dose rate 'FLASH' irradiation in vivo, with an associated reduction in damage burden being reported in vitro. Towards this, two key radiochemical mechanisms have been proposed: radical-radical recombination (RRR) and transient oxygen depletion (TOD), with both being proposed to lead to reduced levels of induced damage. Previously, we reported that FLASH induces lower levels of DNA strand break damage in whole-blood peripheral blood lymphocytes (WB-PBL) ex vivo, but our study failed to distinguish the mechanism(s) involved. A potential outcome of RRR is the formation of crosslink damage (particularly, if any organic radicals recombine), whilst a possible outcome of TOD is a more anoxic profile of induced damage resulting from FLASH. Therefore, the aim of the current study was to profile FLASH-induced damage via the Comet assay, assessing any DNA crosslink formation as a putative marker of RRR and/or anoxic DNA damage formation as an indicative marker of TOD, to determine the extent to which either mechanism contributes to the "FLASH effect". Following FLASH irradiation, we see no evidence of any crosslink formation; however, FLASH irradiation induces a more anoxic profile of induced damage, supporting the TOD mechanism. Furthermore, treatment of WB-PBLs pre-irradiation with BSO abrogates the reduced strand break damage burden mediated by FLASH exposures. In summary, we do not see any experimental evidence to support the RRR mechanism contributing to the reduced damage burden induced by FLASH. However, the observation of a greater anoxic profile of damage following FLASH irradiation, together with the BSO abrogation of the reduced strand break damage burden mediated by FLASH, lends further support to TOD being a driver of the reduced damage burden plus a change in the damage profile mediated by FLASH.
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Affiliation(s)
- Christian R. Cooper
- Leicester Cancer Research Centre, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester LE2 7LX, UK; (D.J.L.J.); (G.D.D.J.)
- MRC Oxford Institute for Radiation Oncology, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, UK
| | - Donald J. L. Jones
- Leicester Cancer Research Centre, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester LE2 7LX, UK; (D.J.L.J.); (G.D.D.J.)
| | - George D. D. Jones
- Leicester Cancer Research Centre, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester LE2 7LX, UK; (D.J.L.J.); (G.D.D.J.)
| | - Kristoffer Petersson
- MRC Oxford Institute for Radiation Oncology, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, UK
- Department of Haematology, Oncology and Radiation Physics, Skåne University Hospital Lund University, 221 85 Lund, Sweden
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Klett KC, Martin-Villa BC, Villarreal VS, Melemenidis S, Viswanathan V, Manjappa R, Ashraf MR, Soto L, Lau B, Dutt S, Rankin EB, Loo BW, Heilshorn SC. Human enteroids as a tool to study conventional and ultra-high dose rate radiation. Integr Biol (Camb) 2023; 15:zyad013. [PMID: 37874173 PMCID: PMC10594601 DOI: 10.1093/intbio/zyad013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 09/22/2023] [Accepted: 09/26/2023] [Indexed: 10/25/2023]
Abstract
Radiation therapy, one of the most effective therapies to treat cancer, is highly toxic to healthy tissue. The delivery of radiation at ultra-high dose rates, FLASH radiation therapy (FLASH), has been shown to maintain therapeutic anti-tumor efficacy while sparing normal tissues compared to conventional dose rate irradiation (CONV). Though promising, these studies have been limited mainly to murine models. Here, we leveraged enteroids, three-dimensional cell clusters that mimic the intestine, to study human-specific tissue response to radiation. We observed enteroids have a greater colony growth potential following FLASH compared with CONV. In addition, the enteroids that reformed following FLASH more frequently exhibited proper intestinal polarity. While we did not observe differences in enteroid damage across groups, we did see distinct transcriptomic changes. Specifically, the FLASH enteroids upregulated the expression of genes associated with the WNT-family, cell-cell adhesion, and hypoxia response. These studies validate human enteroids as a model to investigate FLASH and provide further evidence supporting clinical study of this therapy. Insight Box Promising work has been done to demonstrate the potential of ultra-high dose rate radiation (FLASH) to ablate cancerous tissue, while preserving healthy tissue. While encouraging, these findings have been primarily observed using pre-clinical murine and traditional two-dimensional cell culture. This study validates the use of human enteroids as a tool to investigate human-specific tissue response to FLASH. Specifically, the work described demonstrates the ability of enteroids to recapitulate previous in vivo findings, while also providing a lens through which to probe cellular and molecular-level responses to FLASH. The human enteroids described herein offer a powerful model that can be used to probe the underlying mechanisms of FLASH in future studies.
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Affiliation(s)
- Katarina C Klett
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | | | - Victoria S Villarreal
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA
| | - Stavros Melemenidis
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Vignesh Viswanathan
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Rakesh Manjappa
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - M Ramish Ashraf
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Luis Soto
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Brianna Lau
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Suparna Dutt
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Erinn B Rankin
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Obstetrics and Gynecology, Stanford University School of Medicine, Stanford, CA, USA
- Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Billy W Loo
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
- Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Sarah C Heilshorn
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA
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Verhaegen F, Butterworth KT, Chalmers AJ, Coppes RP, de Ruysscher D, Dobiasch S, Fenwick JD, Granton PV, Heijmans SHJ, Hill MA, Koumenis C, Lauber K, Marples B, Parodi K, Persoon LCGG, Staut N, Subiel A, Vaes RDW, van Hoof S, Verginadis IL, Wilkens JJ, Williams KJ, Wilson GD, Dubois LJ. Roadmap for precision preclinical x-ray radiation studies. Phys Med Biol 2023; 68:06RM01. [PMID: 36584393 DOI: 10.1088/1361-6560/acaf45] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 12/30/2022] [Indexed: 12/31/2022]
Abstract
This Roadmap paper covers the field of precision preclinical x-ray radiation studies in animal models. It is mostly focused on models for cancer and normal tissue response to radiation, but also discusses other disease models. The recent technological evolution in imaging, irradiation, dosimetry and monitoring that have empowered these kinds of studies is discussed, and many developments in the near future are outlined. Finally, clinical translation and reverse translation are discussed.
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Affiliation(s)
- Frank Verhaegen
- MAASTRO Clinic, Radiotherapy Division, GROW-School for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
- SmART Scientific Solutions BV, Maastricht, The Netherlands
| | - Karl T Butterworth
- Patrick G. Johnston, Centre for Cancer Research, Queen's University Belfast, Belfast, Northern Ireland, United Kingdom
| | - Anthony J Chalmers
- School of Cancer Sciences, University of Glasgow, Glasgow G61 1QH, United Kingdom
| | - Rob P Coppes
- Departments of Biomedical Sciences of Cells & Systems, Section Molecular Cell Biology and Radiation Oncology, University Medical Center Groningen, University of Groningen, 9700 AD Groningen, The Netherlands
| | - Dirk de Ruysscher
- MAASTRO Clinic, Radiotherapy Division, GROW-School for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Sophie Dobiasch
- Department of Radiation Oncology, Technical University of Munich (TUM), School of Medicine and Klinikum rechts der Isar, Germany
- Department of Medical Physics, Institute of Radiation Medicine (IRM), Department of Radiation Sciences (DRS), Helmholtz Zentrum München, Germany
| | - John D Fenwick
- Department of Medical Physics & Biomedical Engineering University College LondonMalet Place Engineering Building, London WC1E 6BT, United Kingdom
| | | | | | - Mark A Hill
- MRC Oxford Institute for Radiation Oncology, University of Oxford, ORCRB Roosevelt Drive, Oxford OX3 7DQ, United Kingdom
| | - Constantinos Koumenis
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Kirsten Lauber
- Department of Radiation Oncology, University Hospital, LMU München, Munich, Germany
- German Cancer Consortium (DKTK), Partner site Munich, Germany
| | - Brian Marples
- Department of Radiation Oncology, University of Rochester, NY, United States of America
| | - Katia Parodi
- German Cancer Consortium (DKTK), Partner site Munich, Germany
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München, Garching b. Munich, Germany
| | | | - Nick Staut
- SmART Scientific Solutions BV, Maastricht, The Netherlands
| | - Anna Subiel
- National Physical Laboratory, Medical Radiation Science Hampton Road, Teddington, Middlesex, TW11 0LW, United Kingdom
| | - Rianne D W Vaes
- MAASTRO Clinic, Radiotherapy Division, GROW-School for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | | | - Ioannis L Verginadis
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Jan J Wilkens
- Department of Radiation Oncology, Technical University of Munich (TUM), School of Medicine and Klinikum rechts der Isar, Germany
- Physics Department, Technical University of Munich (TUM), Germany
| | - Kaye J Williams
- Division of Pharmacy and Optometry, University of Manchester, Manchester, United Kingdom
| | - George D Wilson
- Department of Radiation Oncology, Beaumont Health, MI, United States of America
- Henry Ford Health, Detroit, MI, United States of America
| | - Ludwig J Dubois
- The M-Lab, Department of Precision Medicine, GROW-School for Oncology and Reproduction, Maastricht University, Maastricht, The Netherlands
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Liew H, Mein S, Tessonnier T, Abdollahi A, Debus J, Dokic I, Mairani A. Do We Preserve Tumor Control Probability (TCP) in FLASH Radiotherapy? A Model-Based Analysis. Int J Mol Sci 2023; 24:5118. [PMID: 36982185 PMCID: PMC10049554 DOI: 10.3390/ijms24065118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 03/01/2023] [Accepted: 03/02/2023] [Indexed: 03/30/2023] Open
Abstract
Reports of concurrent sparing of normal tissue and iso-effective treatment of tumors at ultra-high dose-rates (uHDR) have fueled the growing field of FLASH radiotherapy. However, iso-effectiveness in tumors is often deduced from the absence of a significant difference in their growth kinetics. In a model-based analysis, we investigate the meaningfulness of these indications for the clinical treatment outcome. The predictions of a previously benchmarked model of uHDR sparing in the "UNIfied and VERSatile bio response Engine" (UNIVERSE) are combined with existing models of tumor volume kinetics as well as tumor control probability (TCP) and compared to experimental data. The potential TCP of FLASH radiotherapy is investigated by varying the assumed dose-rate, fractionation schemes and oxygen concentration in the target. The developed framework describes the reported tumor growth kinetics appropriately, indicating that sparing effects could be present in the tumor but might be too small to be detected with the number of animals used. The TCP predictions show the possibility of substantial loss of treatment efficacy for FLASH radiotherapy depending on several variables, including the fractionation scheme, oxygen level, and DNA repair kinetics. The possible loss of TCP should be seriously considered when assessing the clinical viability of FLASH treatments.
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Affiliation(s)
- Hans Liew
- Clinical Cooperation Unit Translational Radiation Oncology, German Cancer Consortium (DKTK) Core-Center Heidelberg, National Center for Tumor Diseases (NCT), Heidelberg University Hospital (UKHD) and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- Division of Molecular and Translational Radiation Oncology, Heidelberg Faculty of Medicine (MFHD) and Heidelberg University Hospital (UKHD), Heidelberg Ion-Beam Therapy Center (HIT), 69120 Heidelberg, Germany
- Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Oncology (NCRO), Heidelberg University Hospital and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Stewart Mein
- Clinical Cooperation Unit Translational Radiation Oncology, German Cancer Consortium (DKTK) Core-Center Heidelberg, National Center for Tumor Diseases (NCT), Heidelberg University Hospital (UKHD) and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- Division of Molecular and Translational Radiation Oncology, Heidelberg Faculty of Medicine (MFHD) and Heidelberg University Hospital (UKHD), Heidelberg Ion-Beam Therapy Center (HIT), 69120 Heidelberg, Germany
- Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Oncology (NCRO), Heidelberg University Hospital and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA 19104-6303, USA
| | - Thomas Tessonnier
- Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany
| | - Amir Abdollahi
- Clinical Cooperation Unit Translational Radiation Oncology, German Cancer Consortium (DKTK) Core-Center Heidelberg, National Center for Tumor Diseases (NCT), Heidelberg University Hospital (UKHD) and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- Division of Molecular and Translational Radiation Oncology, Heidelberg Faculty of Medicine (MFHD) and Heidelberg University Hospital (UKHD), Heidelberg Ion-Beam Therapy Center (HIT), 69120 Heidelberg, Germany
- Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Oncology (NCRO), Heidelberg University Hospital and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Jürgen Debus
- Division of Molecular and Translational Radiation Oncology, Heidelberg Faculty of Medicine (MFHD) and Heidelberg University Hospital (UKHD), Heidelberg Ion-Beam Therapy Center (HIT), 69120 Heidelberg, Germany
- Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Oncology (NCRO), Heidelberg University Hospital and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- Department of Radiation Oncology, Heidelberg Institute of Radiation Oncology (HIRO), University Hospital Heidelberg, National Center for Tumor Diseases (NCT), 69120 Heidelberg, Germany
- Clinical Cooperation Unit Radiation Oncology, German Cancer Consortium (DKTK) Core-Center Heidelberg, National Center for Tumor Diseases (NCT), Heidelberg University Hospital (UKHD) and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Ivana Dokic
- Clinical Cooperation Unit Translational Radiation Oncology, German Cancer Consortium (DKTK) Core-Center Heidelberg, National Center for Tumor Diseases (NCT), Heidelberg University Hospital (UKHD) and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- Division of Molecular and Translational Radiation Oncology, Heidelberg Faculty of Medicine (MFHD) and Heidelberg University Hospital (UKHD), Heidelberg Ion-Beam Therapy Center (HIT), 69120 Heidelberg, Germany
- Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Oncology (NCRO), Heidelberg University Hospital and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Andrea Mairani
- Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital, 69120 Heidelberg, Germany
- Medical Physics Unit, National Centre of Oncological Hadrontherapy (CNAO), 27100 Pavia, Italy
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Oberoi S, Choy E, Chen YL, Scharschmidt T, Weiss AR. Trimodality Treatment of Extremity Soft Tissue Sarcoma: Where Do We Go Now? Curr Treat Options Oncol 2023; 24:300-326. [PMID: 36877374 DOI: 10.1007/s11864-023-01059-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/23/2023] [Indexed: 03/07/2023]
Abstract
OPINION STATEMENT Extremity soft tissue sarcoma (ESTS) constitutes the majority of patients with soft tissue sarcoma (STS). Patients with localized high-grade ESTS > 5 cm in size carry a substantial risk of developing distant metastasis on follow-up. A neoadjuvant chemoradiotherapy approach can enhance local control by facilitating resection of the large and deep locally advanced tumors while trying to address distant spread by treating the micrometastasis for these high-risk ESTS. Preoperative chemoradiotherapy and adjuvant chemotherapy are often used for children with intermediate- or high-risk non-rhabdomyosarcoma soft tissue tumors in North America and Europe. In adults, the cumulative evidence supporting preoperative chemoradiotherapy or adjuvant chemotherapy remains controversial. However, some studies support a possible benefit of 10% in overall survival (OS) for high-risk localized ESTS, especially for those with a probability of 10-year OS < 60% using validated nomograms. Opponents of neoadjuvant chemotherapy argue that it delays curative surgery, compromises local control, and increases the rate of wound complications and treatment-related mortality; however, the published trials do not support these arguments. Most treatment-related side effects can be managed with adequate supportive care. A coordinated multidisciplinary approach involving sarcoma expertise in surgery, radiation, and chemotherapy is required to achieve better outcomes for ESTS. The next generation of clinical trials will shed light on how comprehensive molecular characterization, targeted agents and/or immunotherapy can be integrated into the upfront trimodality treatment to improve outcomes. To that end, every effort should be made to enroll these patients on clinical trials, when available.
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Affiliation(s)
- Sapna Oberoi
- Department of Pediatric Hematology Oncology, CancerCare Manitoba, Winnipeg, MB, Canada
| | - Edwin Choy
- Division of Medical Oncology, Massachusetts General Hospital, Boston, MA, USA
| | - Yen-Lin Chen
- Department of Orthopedics, Division of Musculoskeletal Oncology, The Ohio State University, Columbus, OH, USA
| | - Thomas Scharschmidt
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA, USA
| | - Aaron R Weiss
- Department of Pediatric Hematology Oncology, Maine Medical Center, 100 Campus Drive, Suite 107 Scarborough, Portland, ME, USA.
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Cucinotta FA, Smirnova OA. Effects of Flash Radiotherapy on Blood Lymphocytes in Humans and Small Laboratory Animals. Radiat Res 2023; 199:240-251. [PMID: 36693147 DOI: 10.1667/rade-22-00093.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Accepted: 12/21/2022] [Indexed: 01/26/2023]
Abstract
A mathematical model, which describes the level of surviving lymphocytes in the blood after ultra-high (FLASH) and lower dose rates of partial-body irradiation, is developed. The model is represented by simple analytic formulae that involve a few parameters, namely, physiologic parameters (characteristics of the blood flow through the blood circulatory system and its irradiated part), a biophysical parameter (a characteristic of the blood lymphocytes radiosensitivity), and the physical parameters (characteristics of irradiation). The model predicts that the level of surviving blood lymphocytes increases as the dose rate increases and approaches the limiting level of (1 - vR), where vR is the fraction of the blood volume in the irradiated part of the blood circulatory system. The model also predicts that the level of surviving blood lymphocytes after the same exposure is higher for lower vR. It is found that FLASH irradiation in humans with doses of 10 to 40 Gy and with exposure times significantly less (<1 s) than the blood circulation time (∼60 s) leads to the maximal blood lymphocyte sparing. Simple formula, which determines effective dose rates for optimal blood lymphocyte sparing, is derived in the framework of the developed model. For the dose range specified above, the obtained modeling prediction of the range of effective dose rates for optimal blood lymphocyte sparing in humans (namely, N ≥40 Gy/s) coincides with the dose rate range in FLASH radiation therapy. It is revealed that the respective effective dose rates for mice are higher than those for humans (for the same dose range) due to the shorter blood circulation time in mice than in humans. Proceeding from the findings obtained in this paper, a hypothesis elucidating the mechanisms of the abscopal effect of FLASH radiation therapy (namely, an antitumor response on metastases located outside of irradiated part of a body) is proposed.
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José Santo R, Habraken SJM, Breedveld S, Hoogeman MS. Pencil-beam Delivery Pattern Optimization Increases Dose Rate for Stereotactic FLASH Proton Therapy. Int J Radiat Oncol Biol Phys 2023; 115:759-767. [PMID: 36057377 DOI: 10.1016/j.ijrobp.2022.08.053] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 08/15/2022] [Accepted: 08/22/2022] [Indexed: 02/04/2023]
Abstract
PURPOSE FLASH dose rates >40 Gy/s are readily available in proton therapy (PT) with cyclotron-accelerated beams and pencil-beam scanning (PBS). The PBS delivery pattern will affect the local dose rate, as quantified by the PBS dose rate (PBS-DR), and therefore needs to be accounted for in FLASH-PT with PBS, but it is not yet clear how. Our aim was to optimize patient-specific scan patterns for stereotactic FLASH-PT of early-stage lung cancer and lung metastases, maximizing the volume irradiated with PBS-DR >40 Gy/s of the organs at risk voxels irradiated to >8 Gy (FLASH coverage). METHODS AND MATERIALS Plans to 54 Gy/3 fractions with 3 equiangular coplanar 244 MeV proton shoot-through transmission beams for 20 patients were optimized with in-house developed software. Planning target volume-based planning with a 5 mm margin was used. Planning target volume ranged from 4.4 to 84 cc. Scan-pattern optimization was performed with a Genetic Algorithm, run in parallel for 20 independent populations (islands). Mapped crossover, inversion, swap, and shift operators were applied to achieve (local) optimality on each island, with migration between them for global optimality. The cost function was chosen to maximize the FLASH coverage per beam at >8 Gy, >40 Gy/s, and 40 nA beam current. The optimized patterns were evaluated on FLASH coverage, PBS-DR distribution, and population PBS-DR-volume histograms, compared with standard line-by-line scanning. Robustness against beam current variation was investigated. RESULTS The optimized patterns have a snowflake-like structure, combined with outward swirling for larger targets. A population median FLASH coverage of 29.0% was obtained for optimized patterns compared with 6.9% for standard patterns, illustrating a significant increase in FLASH coverage for optimized patterns. For beam current variations of 5 nA, FLASH coverage varied between -6.1%-point and 2.2%-point for optimized patterns. CONCLUSIONS Significant improvements on the PBS-DR and, hence, on FLASH coverage and potential healthy-tissue sparing are obtained by sequential scan-pattern optimization. The optimizer is flexible and may be further fine-tuned, based on the exact conditions for FLASH.
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Affiliation(s)
- Rodrigo José Santo
- Erasmus MC Cancer Institute, University Medical Center Rotterdam, Department of Radiotherapy, Rotterdam, The Netherlands; Instituto Superior Técnico, Department of Physics, Universidade de Lisboa, Lisbon, Portugal; Holland Proton Therapy Center, Department of Medical Physics & Informatics, Delft, The Netherlands
| | - Steven J M Habraken
- Erasmus MC Cancer Institute, University Medical Center Rotterdam, Department of Radiotherapy, Rotterdam, The Netherlands; Holland Proton Therapy Center, Department of Medical Physics & Informatics, Delft, The Netherlands.
| | - Sebastiaan Breedveld
- Erasmus MC Cancer Institute, University Medical Center Rotterdam, Department of Radiotherapy, Rotterdam, The Netherlands
| | - Mischa S Hoogeman
- Erasmus MC Cancer Institute, University Medical Center Rotterdam, Department of Radiotherapy, Rotterdam, The Netherlands; Holland Proton Therapy Center, Department of Medical Physics & Informatics, Delft, The Netherlands
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Zhang Q, Gerweck LE, Cascio E, Yang Q, Huang P, Niemierko A, Bertolet A, Nesteruk KP, McNamara A, Schuemann J. Proton FLASH effects on mouse skin at different oxygen tensions. Phys Med Biol 2023; 68:055010. [PMID: 36731139 DOI: 10.1088/1361-6560/acb888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 02/02/2023] [Indexed: 02/04/2023]
Abstract
Objective. Irradiation at FLASH dose rates (>40 Gy s-1) has received great attention due to its reported normal tissue sparing effect. The FLASH effect was originally observed in electron irradiations but has since been shown to also occur with both photon and proton beams. Several mechanisms have been proposed to explain the tissue sparing at high dose rates, including effects involving oxygen, such as depletion of oxygen within the irradiated cells. In this study, we investigated the protective role of FLASH proton irradiation on the skin when varying the oxygen concentration.Approach. Our double scattering proton system provided a 1.2 × 1.6 cm2elliptical field at a dose rate of ∼130 Gy s-1. The conventional dose rate was ∼0.4 Gy s-1. The legs of the FVB/N mice were marked with two tattooed dots and fixed in a holder for exposure. To alter the skin oxygen concentration, the mice were breathing pure oxygen or had their legs tied to restrict blood flow. The distance between the two dots was measured to analyze skin contraction over time.Main results. FLASH irradiation mitigated skin contraction by 15% compared to conventional dose rate irradiation. The epidermis thickness and collagen deposition at 75 d following 25 to 30 Gy exposure suggested a long-term protective function in the skin from FLASH irradiation. Providing the mice with oxygen or reducing the skin oxygen concentration removed the dose-rate-dependent difference in response.Significance. FLASH proton irradiation decreased skin contraction, epidermis thickness and collagen deposition compared to standard dose rate irradiations. The observed oxygen-dependence of the FLASH effect is consistent with, but not conclusive of, fast oxygen depletion during the exposure.
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Affiliation(s)
- Qixian Zhang
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Leo E Gerweck
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Ethan Cascio
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Qingyuan Yang
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Peigen Huang
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Andrzej Niemierko
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Alejandro Bertolet
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Konrad Pawel Nesteruk
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Aimee McNamara
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - Jan Schuemann
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
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Mascia AE, Daugherty EC, Zhang Y, Lee E, Xiao Z, Sertorio M, Woo J, Backus LR, McDonald JM, McCann C, Russell K, Levine L, Sharma RA, Khuntia D, Bradley JD, Simone CB, Perentesis JP, Breneman JC. Proton FLASH Radiotherapy for the Treatment of Symptomatic Bone Metastases: The FAST-01 Nonrandomized Trial. JAMA Oncol 2023; 9:62-69. [PMID: 36273324 PMCID: PMC9589460 DOI: 10.1001/jamaoncol.2022.5843] [Citation(s) in RCA: 62] [Impact Index Per Article: 62.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Accepted: 09/26/2022] [Indexed: 01/24/2023]
Abstract
Importance To our knowledge, there have been no clinical trials of ultra-high-dose-rate radiotherapy delivered at more than 40 Gy/sec, known as FLASH therapy, nor first-in-human use of proton FLASH. Objectives To assess the clinical workflow feasibility and treatment-related toxic effects of FLASH and pain relief at the treatment sites. Design, Setting, and Participants In the FAST-01 nonrandomized trial, participants treated at Cincinnati Children's/UC Health Proton Therapy Center underwent palliative FLASH radiotherapy to extremity bone metastases. Patients 18 years and older with 1 to 3 painful extremity bone metastases and life expectancies of 2 months or more were eligible. Patients were excluded if they had foot, hand, and wrist metastases; metastases locally treated in the 2 weeks prior; metal implants in the treatment field; known enhanced tissue radiosensitivity; and implanted devices at risk of malfunction with radiotherapy. One of 11 patients who consented was excluded based on eligibility. The end points were evaluated at 3 months posttreatment, and patients were followed up through death or loss to follow-up for toxic effects and pain assessments. Of the 10 included patients, 2 died after the 2-month follow-up but before the 3-month follow-up; 8 participants completed the 3-month evaluation. Data were collected from November 3, 2020, to January 28, 2022, and analyzed from January 28, 2022, to September 1, 2022. Interventions Bone metastases were treated on a FLASH-enabled (≥40 Gy/sec) proton radiotherapy system using a single-transmission proton beam. This is consistent with standard of care using the same prescription (8 Gy in a single fraction) but on a conventional-dose-rate (approximately 0.03 Gy/sec) photon radiotherapy system. Main Outcome and Measures Main outcomes included patient time on the treatment couch, device-related treatment delays, adverse events related to FLASH, patient-reported pain scores, and analgesic use. Results A total of 10 patients (age range, 27-81 years [median age, 63 years]; 5 [50%] male) underwent FLASH radiotherapy at 12 metastatic sites. There were no FLASH-related technical issues or delays. The average (range) time on the treatment couch was 18.9 (11-33) minutes per patient and 15.8 (11-22) minutes per treatment site. Median (range) follow-up was 4.8 (2.3-13.0) months. Adverse events were mild and consistent with conventional radiotherapy. Transient pain flares occurred in 4 of the 12 treated sites (33%). In 8 of the 12 sites (67%) patients reported pain relief, and in 6 of the 12 sites (50%) patients reported a complete response (no pain). Conclusions and Relevance In this nonrandomized trial, clinical workflow metrics, treatment efficacy, and safety data demonstrated that ultra-high-dose-rate proton FLASH radiotherapy was clinically feasible. The treatment efficacy and the profile of adverse events were comparable with those of standard-of-care radiotherapy. These findings support the further exploration of FLASH radiotherapy in patients with cancer. Trial Registration ClinicalTrials.gov Identifier: NCT04592887.
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Affiliation(s)
- Anthony E. Mascia
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital, Cincinnati, Ohio
- Department of Radiation Oncology, College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Emily C. Daugherty
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital, Cincinnati, Ohio
- Department of Radiation Oncology, College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Yongbin Zhang
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital, Cincinnati, Ohio
- Department of Radiation Oncology, College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Eunsin Lee
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital, Cincinnati, Ohio
- Department of Radiation Oncology, College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Zhiyan Xiao
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital, Cincinnati, Ohio
- Department of Radiation Oncology, College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Mathieu Sertorio
- Department of Radiation Oncology, College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Jennifer Woo
- Varian Medical Systems, Siemens Healthineers, Palo Alto, California
| | - Lori R. Backus
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital, Cincinnati, Ohio
| | - Julie M. McDonald
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital, Cincinnati, Ohio
| | - Claire McCann
- Varian Medical Systems, Siemens Healthineers, Palo Alto, California
| | - Kenneth Russell
- Varian Medical Systems, Siemens Healthineers, Palo Alto, California
| | - Lisa Levine
- Varian Medical Systems, Siemens Healthineers, Palo Alto, California
| | - Ricky A. Sharma
- Varian Medical Systems, Siemens Healthineers, Palo Alto, California
| | - Dee Khuntia
- Varian Medical Systems, Siemens Healthineers, Palo Alto, California
| | - Jeffrey D. Bradley
- Department of Radiation Oncology, Emory University School of Medicine, Atlanta, Georgia
| | - Charles B. Simone
- Department of Radiation Oncology, New York Proton Center, New York, New York
| | - John P. Perentesis
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital, Cincinnati, Ohio
| | - John C. Breneman
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital, Cincinnati, Ohio
- Department of Radiation Oncology, College of Medicine, University of Cincinnati, Cincinnati, Ohio
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Calvo FA, Ayestaran A, Serrano J, Cambeiro M, Palma J, Meiriño R, Morcillo MA, Lapuente F, Chiva L, Aguilar B, Azcona D, Pedrero D, Pascau J, Delgado JM, Aristu J, Prezado Y. Practice-oriented solutions integrating intraoperative electron irradiation and personalized proton therapy for recurrent or unresectable cancers: Proof of concept and potential for dual FLASH effect. Front Oncol 2022; 12:1037262. [PMID: 36452493 PMCID: PMC9703091 DOI: 10.3389/fonc.2022.1037262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 10/26/2022] [Indexed: 11/15/2022] Open
Abstract
Background Oligo-recurrent disease has a consolidated evidence of long-term surviving patients due to the use of intense local cancer therapy. The latter combines real-time surgical exploration/resection with high-energy electron beam single dose of irradiation. This results in a very precise radiation dose deposit, which is an essential element of contemporary multidisciplinary individualized oncology. Methods Patient candidates to proton therapy were evaluated in Multidisciplinary Tumor Board to consider improved treatment options based on the institutional resources and expertise. Proton therapy was delivered by a synchrotron-based pencil beam scanning technology with energy levels from 70.2 to 228.7 MeV, whereas intraoperative electrons were generated in a miniaturized linear accelerator with dose rates ranging from 22 to 36 Gy/min (at Dmax) and energies from 6 to 12 MeV. Results In a period of 24 months, 327 patients were treated with proton therapy: 218 were adults, 97 had recurrent cancer, and 54 required re-irradiation. The specific radiation modalities selected in five cases included an integral strategy to optimize the local disease management by the combination of surgery, intraoperative electron boost, and external pencil beam proton therapy as components of the radiotherapy management. Recurrent cancer was present in four cases (cervix, sarcoma, melanoma, and rectum), and one patient had a primary unresectable locally advanced pancreatic adenocarcinoma. In re-irradiated patients (cervix and rectum), a tentative radical total dose was achieved by integrating beams of electrons (ranging from 10- to 20-Gy single dose) and protons (30 to 54-Gy Relative Biological Effectiveness (RBE), in 10-25 fractions). Conclusions Individual case solution strategies combining intraoperative electron radiation therapy and proton therapy for patients with oligo-recurrent or unresectable localized cancer are feasible. The potential of this combination can be clinically explored with electron and proton FLASH beams.
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Affiliation(s)
- Felipe A Calvo
- Department of Radiation Oncology, Clinica Universidad de Navarra, Madrid, Spain
| | - Adriana Ayestaran
- Department of Radiation Oncology, Clinica Universidad de Navarra, Madrid, Spain
| | - Javier Serrano
- Department of Radiation Oncology, Clinica Universidad de Navarra, Madrid, Spain
| | - Mauricio Cambeiro
- Department of Radiation Oncology, Clinica Universidad de Navarra, Madrid, Spain
| | - Jacobo Palma
- Department of Radiation Oncology, Clinica Universidad de Navarra, Madrid, Spain
| | - Rosa Meiriño
- Department of Radiation Oncology, Clinica Universidad de Navarra, Madrid, Spain
| | - Miguel A Morcillo
- Medical Applications Unit, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain
| | - Fernando Lapuente
- Department of Surgery, Clinica Universidad de Navarra, Madrid, Spain
| | - Luis Chiva
- Department of Gynecology and Obstretics, Clinica Universidad de Navarra, Madrid, Spain
| | - Borja Aguilar
- Department of Medical Physics, Clinica Universidad de Navarra, Madrid, Spain
| | - Diego Azcona
- Department of Medical Physics, Clinica Universidad de Navarra, Madrid, Spain
| | - Diego Pedrero
- Department of Medical Physics, Clinica Universidad de Navarra, Madrid, Spain
| | - Javier Pascau
- Department of Bioengineering and Aerospace Engineering, Universidad Carlos III de Madrid, Madrid, Spain
| | - José Miguel Delgado
- Department of Radiation Oncology, Clinica Universidad de Navarra, Madrid, Spain
| | - Javier Aristu
- Department of Radiation Oncology, Clinica Universidad de Navarra, Madrid, Spain
| | - Yolanda Prezado
- Translational Research Department. Institut Curie, Université PSL, CNRS UMR, Inserm, Signalisation, Radiobiologie et Cancer, Orsay, France.,Université Paris-Saclay, CNRS UMR, Inserm, Signalisation, Radiobiologie et Cancer, Orsay, France
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FLASHlab@PITZ: New R&D platform with unique capabilities for electron FLASH and VHEE radiation therapy and radiation biology under preparation at PITZ. Phys Med 2022; 104:174-187. [PMID: 36463582 DOI: 10.1016/j.ejmp.2022.10.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 09/19/2022] [Accepted: 10/31/2022] [Indexed: 12/03/2022] Open
Abstract
At the Photo Injector Test facility at DESY in Zeuthen (PITZ), an R&D platform for electron FLASH and very high energy electron radiation therapy and radiation biology is being prepared (FLASHlab@PITZ). The beam parameters available at PITZ are worldwide unique. They are based on experiences from 20 + years of developing high brightness beam sources and an ultra-intensive THz light source demonstrator for ps scale electron bunches with up to 5 nC bunch charge at MHz repetition rate in bunch trains of up to 1 ms length, currently 22 MeV (upgrade to 250 MeV planned). Individual bunches can provide peak dose rates up to 1014 Gy/s, and 10 Gy can be delivered within picoseconds. Upon demand, each bunch of the bunch train can be guided to a different transverse location, so that either a "painting" with micro beams (comparable to pencil beam scanning in proton therapy) or a cumulative increase of absorbed dose, using a wide beam distribution, can be realized at the tumor. Full tumor treatment can hence be completed within 1 ms, mitigating organ movement issues. With extremely flexible beam manipulation capabilities, FLASHlab@PITZ will cover the current parameter range of successfully demonstrated FLASH effects and extend the parameter range towards yet unexploited short treatment times and high dose rates. A summary of the plans for FLASHlab@PITZ and the status of its realization will be presented.
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Lv Y, Lv Y, Wang Z, Lan T, Feng X, Chen H, Zhu J, Ma X, Du J, Hou G, Liao W, Yuan K, Wu H. FLASH radiotherapy: A promising new method for radiotherapy. Oncol Lett 2022; 24:419. [PMID: 36284652 PMCID: PMC9580247 DOI: 10.3892/ol.2022.13539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 08/10/2022] [Indexed: 11/06/2022] Open
Abstract
Among the treatments for malignant tumors, radiotherapy is of great significance both as a main treatment and as an adjuvant treatment. Radiation therapy damages cancer cells with ionizing radiation, leading to their death. However, radiation-induced toxicity limits the dose delivered to the tumor, thereby constraining the control effect of radiotherapy on tumor growth. In addition, the delayed toxicity caused by radiotherapy significantly harms the physical and mental health of patients. FLASH-RT, an emerging class of radiotherapy, causes a phenomenon known as the 'FLASH effect', which delivers radiotherapy at an ultra-high dose rate with lower toxicity to normal tissue than conventional radiotherapy to achieve local tumor control. Although its mechanism remains to be fully elucidated, this modality constitutes a potential new approach to treating malignant tumors. In the present review, the current research progress of FLASH-RT and its various particular effects are described, including the status of research on FLASH-RT and its influencing factors. The hypothetic mechanism of action of FLASH-RT is also summarized, providing insight into future tumor treatments.
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Affiliation(s)
- Yinghao Lv
- Department of Liver Surgery and Liver Transplantation, State Key Laboratory of Biotherapy and Cancer Center, Sichuan University and Collaborative Innovation Center of Biotherapy, West China Hospital, Chengdu, Sichuan 610000, P.R. China
| | - Yue Lv
- Department of Liver Surgery and Liver Transplantation, State Key Laboratory of Biotherapy and Cancer Center, Sichuan University and Collaborative Innovation Center of Biotherapy, West China Hospital, Chengdu, Sichuan 610000, P.R. China
| | - Zhen Wang
- Department of Liver Surgery and Liver Transplantation, State Key Laboratory of Biotherapy and Cancer Center, Sichuan University and Collaborative Innovation Center of Biotherapy, West China Hospital, Chengdu, Sichuan 610000, P.R. China
- Laboratory of Liver Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610000, P.R. China
| | - Tian Lan
- Department of Liver Surgery and Liver Transplantation, State Key Laboratory of Biotherapy and Cancer Center, Sichuan University and Collaborative Innovation Center of Biotherapy, West China Hospital, Chengdu, Sichuan 610000, P.R. China
| | - Xuping Feng
- Laboratory of Liver Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610000, P.R. China
| | - Hao Chen
- Department of Liver Surgery and Liver Transplantation, State Key Laboratory of Biotherapy and Cancer Center, Sichuan University and Collaborative Innovation Center of Biotherapy, West China Hospital, Chengdu, Sichuan 610000, P.R. China
| | - Jiang Zhu
- Department of Liver Surgery and Liver Transplantation, State Key Laboratory of Biotherapy and Cancer Center, Sichuan University and Collaborative Innovation Center of Biotherapy, West China Hospital, Chengdu, Sichuan 610000, P.R. China
| | - Xiao Ma
- Department of Liver Surgery and Liver Transplantation, State Key Laboratory of Biotherapy and Cancer Center, Sichuan University and Collaborative Innovation Center of Biotherapy, West China Hospital, Chengdu, Sichuan 610000, P.R. China
| | - Jinpeng Du
- Department of Liver Surgery and Liver Transplantation, State Key Laboratory of Biotherapy and Cancer Center, Sichuan University and Collaborative Innovation Center of Biotherapy, West China Hospital, Chengdu, Sichuan 610000, P.R. China
| | - Guimin Hou
- Department of Liver Surgery and Liver Transplantation, State Key Laboratory of Biotherapy and Cancer Center, Sichuan University and Collaborative Innovation Center of Biotherapy, West China Hospital, Chengdu, Sichuan 610000, P.R. China
| | - Wenwei Liao
- Department of Liver Surgery and Liver Transplantation, State Key Laboratory of Biotherapy and Cancer Center, Sichuan University and Collaborative Innovation Center of Biotherapy, West China Hospital, Chengdu, Sichuan 610000, P.R. China
| | - Kefei Yuan
- Department of Liver Surgery and Liver Transplantation, State Key Laboratory of Biotherapy and Cancer Center, Sichuan University and Collaborative Innovation Center of Biotherapy, West China Hospital, Chengdu, Sichuan 610000, P.R. China
- Laboratory of Liver Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610000, P.R. China
| | - Hong Wu
- Department of Liver Surgery and Liver Transplantation, State Key Laboratory of Biotherapy and Cancer Center, Sichuan University and Collaborative Innovation Center of Biotherapy, West China Hospital, Chengdu, Sichuan 610000, P.R. China
- Laboratory of Liver Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610000, P.R. China
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Zou W, Kim H, Diffenderfer ES, Carlson DJ, Koch CJ, Xiao Y, Teo BK, Kim MM, Metz JM, Fan Y, Maity A, Koumenis C, Busch TM, Wiersma R, Cengel KA, Dong L. A phenomenological model of proton FLASH oxygen depletion effects depending on tissue vasculature and oxygen supply. Front Oncol 2022; 12:1004121. [PMID: 36518319 PMCID: PMC9742361 DOI: 10.3389/fonc.2022.1004121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 10/11/2022] [Indexed: 11/29/2022] Open
Abstract
Introduction Radiation-induced oxygen depletion in tissue is assumed as a contributor to the FLASH sparing effects. In this study, we simulated the heterogeneous oxygen depletion in the tissue surrounding the vessels and calculated the proton FLASH effective-dose-modifying factor (FEDMF), which could be used for biology-based treatment planning. Methods The dose and dose-weighted linear energy transfer (LET) of a small animal proton irradiator was simulated with Monte Carlo simulation. We deployed a parabolic partial differential equation to account for the generalized radiation oxygen depletion, tissue oxygen diffusion, and metabolic processes to investigate oxygen distribution in 1D, 2D, and 3D solution space. Dose and dose rates, particle LET, vasculature spacing, and blood oxygen supplies were considered. Using a similar framework for the hypoxic reduction factor (HRF) developed previously, the FEDMF was derived as the ratio of the cumulative normoxic-equivalent dose (CNED) between CONV and UHDR deliveries. Results Dynamic equilibrium between oxygen diffusion and tissue metabolism can result in tissue hypoxia. The hypoxic region displayed enhanced radio-resistance and resulted in lower CNED under UHDR deliveries. In 1D solution, comparing 15 Gy proton dose delivered at CONV 0.5 and UHDR 125 Gy/s, 61.5% of the tissue exhibited ≥20% FEDMF at 175 μm vasculature spacing and 18.9 μM boundary condition. This percentage reduced to 34.5% and 0% for 8 and 2 Gy deliveries, respectively. Similar trends were observed in the 3D solution space. The FLASH versus CONV differential effect remained at larger vasculature spacings. A higher FLASH dose rate showed an increased region with ≥20% FEDMF. A higher LET near the proton Bragg peak region did not appear to alter the FLASH effect. Conclusion We developed 1D, 2D, and 3D oxygen depletion simulation process to obtain the dynamic HRF and derive the proton FEDMF related to the dose delivery parameters and the local tissue vasculature information. The phenomenological model can be used to simulate or predict FLASH effects based on tissue vasculature and oxygen concentration data obtained from other experiments.
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Comparison of intratumor and local immune response between MV X-ray FLASH and conventional radiotherapies. Clin Transl Radiat Oncol 2022; 38:138-146. [DOI: 10.1016/j.ctro.2022.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 11/06/2022] [Accepted: 11/07/2022] [Indexed: 11/10/2022] Open
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