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Effectiveness of Flattening-Filter-Free versus Flattened Beams in V79 and Glioblastoma Patient-Derived Stem-like Cells. Int J Mol Sci 2023; 24:ijms24021107. [PMID: 36674623 PMCID: PMC9861147 DOI: 10.3390/ijms24021107] [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: 11/03/2022] [Revised: 12/31/2022] [Accepted: 01/03/2023] [Indexed: 01/09/2023] Open
Abstract
Literature data on the administration of conventional high-dose beams with (FF) or without flattening filters (FFF) show conflicting results on biological effects at the cellular level. To contribute to this field, we irradiated V79 Chinese hamster lung fibroblasts and two patient-derived glioblastoma stem-like cell lines (GSCs-named #1 and #83) using a clinical 10 MV accelerator with FF (at 4 Gy/min) and FFF (at two dose rates 4 and 24 Gy/min). Cell killing and DNA damage induction, determined using the γ-H2AX assay, and gene expression were studied. No significant differences in the early survival of V79 cells were observed as a function of dose rates and FF or FFF beams, while a trend of reduction in late survival was observed at the highest dose rate with the FFF beam. GSCs showed similar survival levels as a function of dose rates, both delivered in the FFF regimen. The amount of DNA damage measured for both dose rates after 2 h was much higher in line #1 than in line #83, with statistically significant differences between the two dose rates only in line #83. The gene expression analysis of the two GSC lines indicates gene signatures mimicking the prognosis of glioblastoma (GBM) patients derived from a public database. Overall, the results support the current use of FFF and highlight the possibility of identifying patients with candidate gene signatures that could benefit from irradiation with FFF beams at a high dose rate.
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Nikolakopoulou A, Peppa V, Alexiou A, Pissakas G, Terzoudi G, Karaiskos P. Comparison and Evaluation of Different Radiotherapy Techniques Using Biodosimetry Based on Cytogenetics. Cancers (Basel) 2021; 14:cancers14010146. [PMID: 35008308 PMCID: PMC8749890 DOI: 10.3390/cancers14010146] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/16/2021] [Accepted: 12/17/2021] [Indexed: 12/25/2022] Open
Abstract
Simple Summary Cell killing and tumor response in cancer patients depends not only on the absorbed radiation dose but also on the dose rate and delivery time. In this study, a biodosimetry assay based on the frequency of dicentrics chromosomes scored in peripheral blood lymphocytes from prostate cancer patients and PC3 human prostate cancer cell line was used to investigate the radiobiological impact of the relative prolonged dose delivery time and/or decreased dose rate met in advanced modulated radiotherapy techniques (VMAT and IMRT) compared to conventional non-modulated (3D-CRT) in prostate patient plan irradiations. The results showed a small but statistically significant decrease in the number of dicentrics following radiation with the modulated techniques, suggesting a corresponding decrease on the radiation dose efficiency. The biodosimetry assay could be used as an alternative to the laborious conventional clonogenic assay, while both lymphocytes and cancer cell line could effectively be used for estimation of the biological absorbed dose. Abstract While rapid technological advances in radiotherapy techniques have led to a more precise delivery of radiation dose and to a decreased risk of side effects, there is still a need to evaluate the efficacy of the new techniques estimating the biological dose and to investigate the radiobiological impact of the protracted radiotherapy treatment duration. The aim of this study is to compare, at a cytogenetic level, advanced radiotherapy techniques VMAT and IMRT with the conventional 3D-CRT, using biological dosimetry. A dicentric biodosimetry assay based on the frequency of dicentrics chromosomes scored in peripheral blood lymphocytes from prostate cancer patients and PC3 human prostate cancer cell line was used. For each patient blood sample and each subpopulation of the cultured cell line, three different irradiations were performed using the 3D-CRT, IMRT, and VMAT technique. The absorbed dose was estimated with the biodosimetry method based on the induced dicentric chromosomes. The results showed a statistically significant underestimation of the biological absorbed dose of ~6% for the IMRT and VMAT compared to 3D-CRT irradiations for peripheral blood lymphocytes, whereas IMRT and VMAT results were comparable without a statistically significant difference, although slightly lower values were observed for VMAT compared to IMRT irradiation. Similar results were obtained using the PC3 cell line. The observed biological dose underestimation could be associated with the relative decreased dose rate and increase irradiation time met in modulated techniques compared to the conventional 3D-CRT irradiations.
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Affiliation(s)
- Aggeliki Nikolakopoulou
- Laboratory of Health Physics, Radiobiology & Cytogenetics, Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, National Centre for Scientific Research ‘‘Demokritos’’, 15310 Athens, Greece; (A.N.); (G.T.)
- Medical Physics Laboratory, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece;
| | - Vasiliki Peppa
- Medical Physics Laboratory, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece;
- Radiotherapy Department, General Hospital of Athens Alexandra, 11528 Athens, Greece; (A.A.); (G.P.)
| | - Antigoni Alexiou
- Radiotherapy Department, General Hospital of Athens Alexandra, 11528 Athens, Greece; (A.A.); (G.P.)
| | - George Pissakas
- Radiotherapy Department, General Hospital of Athens Alexandra, 11528 Athens, Greece; (A.A.); (G.P.)
| | - Georgia Terzoudi
- Laboratory of Health Physics, Radiobiology & Cytogenetics, Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, National Centre for Scientific Research ‘‘Demokritos’’, 15310 Athens, Greece; (A.N.); (G.T.)
| | - Pantelis Karaiskos
- Medical Physics Laboratory, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece;
- Correspondence:
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Kouris P, Moutsatsos A, Pappas EP, Beli I, Pantelakos P, Karaiskos P, Pantelis E. Assessing the dose rate delivery of helical TomoTherapy prostate and head & neck treatments. Biomed Phys Eng Express 2021; 8. [PMID: 34755680 DOI: 10.1088/2057-1976/ac37cb] [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: 06/25/2021] [Accepted: 11/09/2021] [Indexed: 11/11/2022]
Abstract
The dose rate distributions delivered to 55 prostate and head & neck (H&N) cancer patients treated with a helical TomoTherapy (HT) system were resolved and assessed with regard to pitch and field width defined during treatment planning. Statistical analysis of the studied cases showed that the median treatment delivery time was 4.4 min and 6.3 min for the prostate and H&N cases, respectively. Dose rate volume histogram data for the studied cases showed that the 25% and 12% of the volume of the planning target volumes of the prostate and H&N cases are irradiated with a dose rate of greater or equal to 1 Gy min-1. Quartile dose rate (QDR) data confirmed that in HT, where the target is irradiated in slices, most of the dose is delivered to each voxel of the target when it travels within the beam. Analysis of the planning data from all cases showed that this lasts for 68 s (median value). QDRs results showed that using the 2.5 cm field width, 75% of the prescribed dose is delivered to target voxels with a median dose rate of at least 3.2 Gy min-1and 4.5 Gy min-1, for the prostate and H&N cases, respectively. Systematically higher dose rates were observed for the H&N cases due to the shallower depths of the lesions in this anatomical site. Delivered dose rates were also found to increase with field width and pitch setting, due to the higher output of the system which, in general, results in accordingly decreased total treatment time. The biological effect of the dose rate findings of this work needs to be further investigated using in-vitro studies and clinical treatment data.
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Affiliation(s)
- P Kouris
- Medical Physics Laboratory, Medical School, National and Kapodistrian University of Athens, 75 Mikras Asias, 11527 Athens, Greece
| | - A Moutsatsos
- Medical Physics Laboratory, Medical School, National and Kapodistrian University of Athens, 75 Mikras Asias, 11527 Athens, Greece.,Radiotherapy and Radiosurgery Department, Latropolis Clinic, 54-56 Ethnikis Antistaseos, 15231 Athens, Greece
| | - E P Pappas
- Radiotherapy and Radiosurgery Department, Latropolis Clinic, 54-56 Ethnikis Antistaseos, 15231 Athens, Greece
| | - I Beli
- Radiotherapy and Radiosurgery Department, Latropolis Clinic, 54-56 Ethnikis Antistaseos, 15231 Athens, Greece
| | - P Pantelakos
- Radiotherapy and Radiosurgery Department, Latropolis Clinic, 54-56 Ethnikis Antistaseos, 15231 Athens, Greece
| | - P Karaiskos
- Medical Physics Laboratory, Medical School, National and Kapodistrian University of Athens, 75 Mikras Asias, 11527 Athens, Greece
| | - E Pantelis
- Medical Physics Laboratory, Medical School, National and Kapodistrian University of Athens, 75 Mikras Asias, 11527 Athens, Greece.,Radiotherapy and Radiosurgery Department, Latropolis Clinic, 54-56 Ethnikis Antistaseos, 15231 Athens, Greece
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Savanović M, Jaroš D, Foulquier JN. Comparison of Phase-Gated and Amplitude-Gated Dose Delivery to a Moving Target using Gafchromic EBT3 Film. J Med Phys 2021; 46:73-79. [PMID: 34566286 PMCID: PMC8415247 DOI: 10.4103/jmp.jmp_81_20] [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: 09/06/2020] [Revised: 05/19/2021] [Accepted: 05/24/2021] [Indexed: 11/18/2022] Open
Abstract
Introduction: This study compared phase-gated and amplitude-gated dose deliveries to the moving gross tumor volume (GTV) in lung stereotactic body radiation therapy (SBRT) using Gafchromic External Beam Therapy (EBT3) dosimetry film. Materials and Methods: Eighty treatment plans using two techniques (40 phase gated and 40 amplitude gated) were delivered using dynamic conformal arc therapy (DCAT). The GTV motion, breathing amplitude, and period were taken from 40 lung SBRT patients who performed regular breathing. These parameters were re-simulated using a modified Varian breathing mini phantom. The dosimetric accuracy of the phase- and amplitude-gated treatment plans was analyzed using Gafchromic EBT3 dosimetry film. The treatment delivery efficacy was analyzed for gantry rotation, number of monitor unit (MU), and target position per triggering window. The time required to deliver the phase- and amplitude-gated treatment techniques was also evaluated. Results: The mean dose (range) per fraction was 16.11 ± 0.91 Gy (13.04–17.50 Gy) versus 16.26 ± 0.83 Gy (13.82–17.99 Gy) (P < 0.0001) for phase- and amplitude-gated delivery. The greater difference in the gamma passing rate was 1.2% ±0.4% in the amplitude-gated compared to the phase gated. The gantry rotation per triggering time (tt) was 2° ±1° (1.2°–3°) versus 5° ±1° (3°–6°) (P < 0.0001) and MU per tt was 10 ± 3 MU (6–13 MU) versus 24 ± 7 MU (12–32 MU) (P < 0.0001), for phase- versus amplitude-gated techniques. A 90 beam interruption in the phase-gated technique impacted the treatment delivery efficacy, increasing the treatment delivery time in the phase gated for 1664 ± 202 s 1353–1942 s) compared to 36 interruptions in the amplitude gated 823 ± 79 s (712–926 s) (P < 0.0001). Conclusion: Amplitude-gated DCAT allows for better dosimetric accuracy over phase-gated treatment patients with regular breathing patterns.
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Affiliation(s)
- Milovan Savanović
- Faculty of Medicine, University of Paris-Saclay, Le Kremlin-Bicêtre, Paris, France.,Department of Radiation Oncology, Tenon Hospital, APHP, Sorbonne University, Paris, France
| | - Dražan Jaroš
- Center for Radiation Therapy, International Medical Centers, Affidea, Banja Luka, Bosnia and Herzegovina
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Nakano H, Kawahara D, Tanabe S, Utsunomiya S, Takizawa T, Sakai M, Nakano T, Ohta A, Kaidu M, Ishikawa H. Calculated relative biological effectiveness (RBE) for initial DNA double-strand breaks (DSB) from flattening filter and flattening filter-free 6 MV X-ray fields. BJR Open 2021; 3:20200072. [PMID: 34286177 PMCID: PMC8256801 DOI: 10.1259/bjro.20200072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 02/25/2021] [Indexed: 12/14/2022] Open
Abstract
Objectives We evaluated the radiobiological effectiveness based on the yields of DNA double-strand breaks (DSBs) of field induction with flattening filter (FF) and FF-free (FFF) photon beams. Methods We used the particle and heavy ion transport system (PHITS) and a water equivalent phantom (30 × 30 × 30 cm3) to calculate the physical qualities of the dose-mean lineal energy (yD) with 6 MV FF and FFF. The relative biological effectiveness based on the yields of DNA-DSBs (RBEDSB) was calculated for standard radiation such as 220 kVp X-rays by using the estimating yields of SSBs and DSBs. The measurement points used to calculate the in-field yD and RBEDSB were located at a depth of 3, 5, and 10 cm in the water equivalent phantom on the central axis. Measurement points at 6, 8, and 10 cm in the lateral direction of each of the three depths from the central axis were set to calculate the out-of-field yD and RBEDSB. Results The RBEDSB of FFF in-field was 1.7% higher than FF at each measurement depth. The RBEDSB of FFF out-of-field was 1.9 to 6.4% higher than FF at each depth measurement point. As the distance to out-of-field increased, the RBEDSB of FFF rose higher than those of FF. FFF has a larger RBEDSB than FF based on the yields of DNA-DSBs as the distance to out-of-field increased. Conclusions The out-of-field radiobiological effect of FFF could thus be greater than that of FF since the spreading of the radiation dose out-of-field with FFF could be a concern compared to the FF. Advances in knowledge The RBEDSB of FFF of out-of-field might be larger than FF.
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Affiliation(s)
- Hisashi Nakano
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Daisuke Kawahara
- Department of Radiation Oncology, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima-shi, Hiroshima, Japan
| | - Satoshi Tanabe
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Satoru Utsunomiya
- Department of Radiological Technology, Niigata University Graduate School of Health Sciences, 2-746 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | | | - Madoka Sakai
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Toshimichi Nakano
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Atsushi Ohta
- Department of Radiation Oncology, Niigata University Medical and Dental Hospital, 1-757 Asahimachi-dori, Chuo-ku, Niigata, Japan
| | - Motoki Kaidu
- Department of Radiation Oncology, Niigata Neurosurgical Hospital, Niigata, 3057 Yamada, Nishi-ku, Niigata, Japan
| | - Hiroyuki Ishikawa
- Department of Radiation Oncology, Niigata Neurosurgical Hospital, Niigata, 3057 Yamada, Nishi-ku, Niigata, Japan
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6
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Effect of Flattening Filter and Flattening Filter Free beams on radiotherapy-induced peripheral blood cell damage. Radiat Phys Chem Oxf Engl 1993 2021. [DOI: 10.1016/j.radphyschem.2021.109383] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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7
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Aras S, Tanzer İO, Sayir N, Keleş MS, Özgeriş FB. Radiobiological comparison of flattening filter (FF) and flattening filter-free (FFF) beam in rat laryngeal tissue. Int J Radiat Biol 2021; 97:249-255. [PMID: 33320739 DOI: 10.1080/09553002.2021.1857457] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
PURPOSE The purpose of this study is to investigate the radioprotective effect of melatonin by analyzing histopathological changes and serum biochemical levels on experimental rat models exposed to flattening filter (FF) and flattening filter-free (FFF) beam. MATERIALS AND METHODS Forty-eight healthy adult Sprague Dawley rats were randomly divided into six groups. The control (Group 1) was given no treatment, the melatonin (Group 2) was given 10 mg/kg melatonin only, the FF (Group 3) and FFF (Group 5) were given fractionated dose (Total 32 Gy, 5 consecutive days) radiotherapy only, and the FF plus melatonin (Group 4) and FFF plus melatonin (Group 6) were given 10 mg/kg melatonin 15 minutes prior to irradiation. Rats were examined for histopathology and biochemical analysis 10 days after irradiation. RESULTS When results of FF and FFF radiotherapy only groups are compared to control group, statistically significant difference in histopathological and biochemical parameters are observed; however, melatonin administration in radiotherapy plus melatonin groups improved these parameters (p <.05). In addition, there was no statistically significant difference between FF and FFF beams (p > .05). CONCLUSIONS The effect of low- and high-dose beams on the rat larynx and serum samples were investigated histopathologically and biochemically for the first time. We observed that melatonin supplemented before FF and FFF radiotherapy protected early period radiotherapy-induced laryngeal mucosal damage. Since the radiobiological results of FF and FFF beams are similar, FFF beams can be safely applied in laryngeal irradiation. However, more experimental rat and clinical studies are needed to clarify the radiobiological uncertainy concerning dose rate on cancerous and healthy tissue.
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Affiliation(s)
- Serhat Aras
- Medical Imaging Techniques Programme, University of Health Sciences Turkey, Istanbul, Turkey
| | - İhsan Oğuz Tanzer
- Biomedical Technology Programme, University of Health Sciences Turkey, Istanbul, Turkey.,Department of Neuroscience and Biomedical Engineering, Aalto University, Finland
| | - Neslihan Sayir
- Pathology Laboratory Techniques Programme, University of Health Sciences Turkey, Istanbul, Turkey
| | - Mevlüt Sait Keleş
- Department of Medical Biochemistry, Faculty of Medicine, Ataturk University, Erzurum, Turkey
| | - Fatma Betül Özgeriş
- Department of Nutrition and Dietetics, Faculty of Health Sciences, Ataturk University, Erzurum, Turkey
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Pokhrel D, Sanford L, Dhanireddy B, Molloy J, Randall M, McGarry RC. Flattening filter free VMAT for a stereotactic, single-dose of 30 Gy to lung lesion in a 15-min treatment slot. J Appl Clin Med Phys 2020; 21:6-12. [PMID: 32039544 PMCID: PMC7170282 DOI: 10.1002/acm2.12829] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 12/10/2019] [Accepted: 12/18/2019] [Indexed: 12/26/2022] Open
Abstract
Cone‐beam CT‐guided single dose of lung stereotactic body radiotherapy (SBRT) treatment with a flattening filter free (FFF) beam and volumetric modulated arc therapy (VMAT) is a safe and highly effective treatment modality for selective small lung lesions. Four‐dimensional (4D) CT‐based treatment plans were generated using advanced AcurosXB algorithm for heterogeneity corrections. 6X‐FFF beam produced highly conformal radiosurgical dose distribution to the target and reduced lung SBRT fraction duration to less than 10 min for a single dose of 30 Gy, significantly improving patient comfort and clinic workflow. Early follow‐up CT imaging results (mean, 8 months) show high local control rates (100%) with no acute lung or rib toxicity. Longer clinical follow‐up in a larger patient cohort managed in this fashion is underway to further validate this treatment approach.
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Affiliation(s)
- Damodar Pokhrel
- Department of Radiation Medicine, Medical Physics Graduate Program, University of Kentucky, Lexington, KY, USA
| | - Lana Sanford
- Department of Radiation Medicine, Medical Physics Graduate Program, University of Kentucky, Lexington, KY, USA
| | - Bhaswanth Dhanireddy
- Department of Radiation Medicine, Medical Physics Graduate Program, University of Kentucky, Lexington, KY, USA
| | - Janelle Molloy
- Department of Radiation Medicine, Medical Physics Graduate Program, University of Kentucky, Lexington, KY, USA
| | - Marcus Randall
- Department of Radiation Medicine, Medical Physics Graduate Program, University of Kentucky, Lexington, KY, USA
| | - Ronald C McGarry
- Department of Radiation Medicine, Medical Physics Graduate Program, University of Kentucky, Lexington, KY, USA
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Cerviño LI, Soultan D, Advani SJ, Cornell M, Yock A, Pettersson N, Song WY, Aguilera J, Murphy J, Hoh C, James C, Paravati A, Coope R, Gill B, Moiseenko V. An in vitro study for the dosimetric and radiobiological validation of respiratory gating in conventional and hypofractionated radiotherapy of the lung: effect of dose, dose rate, and breathing pattern. Phys Med Biol 2019; 64:135009. [PMID: 31189137 DOI: 10.1088/1361-6560/ab2940] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Stereotactic body radiotherapy (SBRT) of the lung has become a standard of care for early-stage inoperable non-small cell lung cancer (NSCLC). A common strategy to manage respiratory motion is gating, which inevitably results in an increase in treatment time, especially in irregularly-breathing patients. Flattening-filter free (FFF) beams allow for delivery of the treatment at a higher dose rate, therefore counteracting the lengthened treatment time due to frequent interruption of the beam during gated radiotherapy. In this study, we perform our in vitro evaluation of the dosimetric and radiobiological effect of gated lung SBRT with simultaneous integrated boost (SIB) using both flattened and FFF beams. A moving thorax-shaped phantom with inserts and applicators was used for simulation, planning, gated treatment delivery measurements and in vitro tests. The effects of gating window, dose rate, and breathing pattern were evaluated. Planned doses represented a typical conventional fractionation, 200 cGy per fraction with SIB to 240 cGy, flattened beam only, and SBRT, 800 cGy with SIB to 900 cGy, flattened and FFF beams. Ideal, as well as regular and irregular patient-specific breathing patterns with and without gating were used. A survival assay for lung adenocarcinoma A549 cell line was performed. Delivered dose was within 6% for locations planned to receive 200 and 800 cGy and within 4% for SIB locations. Time between first beam-on and last beam-off varied from approximately 1.5 min for conventional fractionation, 200/240 cGy, to 10.5 min for gated SBRT, 800/900 cGy doses, flattened beam and irregular breathing motion pattern. With FFF beams dose delivery time was shorter by a factor of 2-3, depending on the gating window and breathing pattern. We have found that, for the most part, survival depended on dose and not on dose rate, gating window, or breathing regularity.
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Affiliation(s)
- Laura I Cerviño
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA 92093, United States of America. Author to whom correspondence should be addressed
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10
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Hao J, Magnelli A, Godley A, Yu JS. Use of a Linear Accelerator for Conducting In Vitro Radiobiology Experiments. J Vis Exp 2019. [PMID: 31180366 DOI: 10.3791/59514] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Radiation therapy remains one of the cornerstones of cancer management. For most cancers, it is the most effective, nonsurgical therapy to debulk tumors. Here, we describe a method to irradiate cancer cells with a linear accelerator. The advancement of linear accelerator technology has improved the precision and efficiency of radiation therapy. The biological effects of a wide range of radiation doses and dose rates continue to be an intense area of investigation. Use of linear accelerators can facilitate these studies using clinically relevant doses and dose rates.
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Affiliation(s)
- Jing Hao
- Department of Cancer Biology, Cleveland Clinic
| | | | | | - Jennifer S Yu
- Department of Cancer Biology, Cleveland Clinic; Department of Radiation Oncology, Cleveland Clinic;
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11
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The effects of extra high dose rate irradiation on glioma stem-like cells. PLoS One 2018; 13:e0202533. [PMID: 30118510 PMCID: PMC6097670 DOI: 10.1371/journal.pone.0202533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 08/03/2018] [Indexed: 11/19/2022] Open
Abstract
Radiation therapy is an integral part of treatment for patients with glioblastoma. New technological advances in linear accelerators have made extra-high dose rate irradiation possible. This shortens patient treatment time significantly compared to standard dose rate irradiation, but the biologic effects of extra high dose rate irradiation are poorly understood. Glioma stem-like cells (GSCs) are resistant to standard radiation and contribute to tumor progression. Here, we assess the therapeutic effect of extra high dose rate vs. standard dose rate irradiation on GSCs. GSCs were exposed to 2, 4 and 6 Gy X-irradiation at dose rates of 4.2 Gy/min or 21.2 Gy/min (400 monitoring units (MU)/min or 2100 MU/min). We analyzed cell survival with cell growth assays, tumorsphere formation assays and colony formation assays. Cell kill and self-renewal were dependent on the total dose of radiation delivered. However, there was no difference in survival of GSCs or DNA damage repair in GSCs irradiated at different dose rates. GSCs exhibited significant G1 and G2/M phase arrest and increased apoptosis with higher doses of radiation but there was no difference between the two dose rates at each given dose. In a GSC-derived preclinical model of glioblastoma, radiation extended animal survival, but there was no difference in survival in mice receiving different dose rates of radiation. We conclude that GSCs respond to larger fractions of radiation, but extra high dose rate irradiation has no significant biologic advantage in comparison with standard dose rate irradiation.
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Njeh CF, Salmon HW, Schiller C. The Impact of Dose Rate on the Accuracy of Step-and-Shoot Intensity-modulated Radiation Therapy Quality Assurance Using Varian 2300CD. J Med Phys 2018; 42:206-212. [PMID: 29296034 PMCID: PMC5744448 DOI: 10.4103/jmp.jmp_18_17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Introduction Intensity-modulated radiation therapy (IMRT) delivery using "step-and-shoot" technique on Varian C-Series linear accelerator (linac) is influenced by the communication frequency between the multileaf collimator and linac controllers. Hence, the dose delivery accuracy is affected by the dose rate. Aim Our aim was to quantify the impact of using two dose rates on plan quality assurance (QA). Materials and Methods Twenty IMRT patients were selected for this study. The plan QA was measured at two different dose rates. A gamma analysis was performed, and the degree of plan modulation on the QA pass rate was also evaluated in terms of average monitor unit per segment (MU/segment) and the total number of segments. Results The mean percentage gamma pass rate of 94.9% and 93.5% for 300 MU/min and 600 MU/min dose rate, respectively, was observed. There was a significant (P = 0.001) decrease in percentage gamma pass rate when the dose rate was increased from 300 MU/min to 600 MU/min. There was a weak, but significant association between the percentage pass rate at both dose rate and total number of segments. The total number of MU was significantly correlated to the total number of segments (r = 0.59). We found a positive correlation between the percentage pass rate and mean MU/segment, r = 0.52 and r = 0.57 for 300 MU/min and 600 MU/min, respectively. Conclusion IMRT delivery using step-and-shoot technique on Varian 2300CD is impacted by the dose rate and the total amount of segments.
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Affiliation(s)
- Christopher F Njeh
- Diagnostic and Treatment Center, Marshfield Clinic, Weston, WI.,Department of Radiation Oncology, Franciscan St. Francis Health, Indianapolis, IN 46237, USA
| | - Howard W Salmon
- Department of Radiation Oncology, Franciscan St. Francis Health, Indianapolis, IN 46237, USA
| | - Claire Schiller
- Diagnostic and Treatment Center, Marshfield Clinic, Weston, WI
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Rieber J, Tonndorf-Martini E, Schramm O, Rhein B, König L, Adeberg S, Meyerhof E, Mohr A, Kappes J, Hoffmann H, Debus J, Rieken S. Establishing stereotactic body radiotherapy with flattening filter free techniques in the treatment of pulmonary lesions - initial experiences from a single institution. Radiat Oncol 2016; 11:80. [PMID: 27411832 PMCID: PMC4943033 DOI: 10.1186/s13014-016-0648-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 05/17/2016] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Stereotactic body radiotherapy (SBRT) using flattening filter free (FFF)-techniques has been increasingly applied during the last years. However, clinical studies investigating this emerging technique are still rare. Hence, we analyzed toxicity and clinical outcome of pulmonary SBRT with FFF-techniques and performed dosimetric comparison to conventional techniques using flattening filters (FF). MATERIALS AND METHODS Between 05/2014 and 06/2015, 56 consecutive patients with 61 pulmonary lesions were treated with SBRT in FFF-mode. Central lesions received 8 × 7.5 Gy delivered to the conformally enclosing 80 %-isodose, while peripheral lesions were treated with 3 × 15 Gy, prescribed to the 65 %-isodose. Early and late toxicity (after 6 months) as well as initial clinical outcomes were evaluated. Furthermore, [deleted] plan quality and efficiency were evaluated by analyzing conformity, beam- on and total treatment delivery times in comparison to plans with FF-dose application. RESULTS Median follow-up time was 9.3 months (range 1.5-18.0 months). Early toxicity was low with only 5 patients (8.9 %) reporting CTCAE 2° or higher side-effects. Only one patient (1.8 %) was diagnosed with radiation-induced pneumonitis CTCAE 3°, while 2 (3.6 %) patients suffered from pneumonitis CTCAE 2°. After 6 months, no toxicity greater than CTCAE 2° was reported. 1-year local progression-free survival, distant progression-free survival and overall survival were 92.8 %, 78.0 %, and 94.4 %, respectively. While plan quality was similar for FFF- and FF-plans in respect to conformity (p = 0.275), median beam-on time as well as total treatment time were significantly reduced for SBRT in FFF-mode compared to FF-mode (p ≤ 0.001, p ≤ 0.001). CONCLUSIONS Patient treatment with SBRT using FFF-techniques is safe and provides promising clinical results with only modest toxicity at significantly increased dose delivery speed.
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Affiliation(s)
- Juliane Rieber
- Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Eric Tonndorf-Martini
- Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Oliver Schramm
- Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Bernhard Rhein
- Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Laila König
- Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Sebastian Adeberg
- Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Eva Meyerhof
- Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Angela Mohr
- Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Jutta Kappes
- Translational Research Unit, Thoraxklinik, Heidelberg University, Germany Translational Lung Research Centre Heidelberg (TLRC-H), Member of the German Centre for Lung Research (DZL), Heidelberg, Germany.,Department of Pneumology, Thoraxklinik, Heidelberg University, Heidelberg, Germany
| | - Hans Hoffmann
- Department of Pneumology, Thoraxklinik, Heidelberg University, Heidelberg, Germany.,Department of Thoracic Surgery, Thoraxklinik, Heidelberg University, Heidelberg, Germany
| | - Jürgen Debus
- Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Stefan Rieken
- Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany. .,Heidelberg Institute of Radiation Oncology, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.
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Abstract
Human tissues exhibit a varying response to radiation dose depending on the dose rate and fractionation scheme used. Dose rate effects have been reported for different radiations, and tissue types. The literature indicates that there is not a significant difference in response for low-LET radiation when using dose rates between 1 Gy min(-1) and 12 Gy min(-1) but lower dose rates have an observable sparing effect on tissues and a differential effect between tissues. In intensity-modulated radiotherapy such as volumetric modulated arc therapy (VMAT) the dose can be delivered with a wide range of dose rates. In this work we developed a method based on time-resolved Monte Carlo simulations to quantify the dose rate frequency distribution for clinical VMAT treatments for three cancer sites, head and neck, lung, and pelvis within both planning target volumes (PTV) and normal tissues. The results show a wide range of dose rates are used to deliver dose in VMAT and up to 75% of the PTV can have its dose delivered with dose rates <1 Gy min(-1). Pelvic plans on average have a lower mean dose rate within the PTV than lung or head and neck plans but a comparable mean dose rate within the organs at risk. Two VMAT plans that fulfil the same dose objectives and constraints may be delivered with different dose rate distributions, particularly when comparing single arcs to multiple arc plans. It is concluded that for dynamic plans, the dose rate range used varies to a larger degree than previously assumed. The effect of the dose rate range in VMAT on clinical outcome is unknown.
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Affiliation(s)
- Mark Podesta
- Department of Radiation Oncology (MAASTRO), Maastricht University Medical Center (MUMC), Maastricht, The Netherlands
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15
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Dubois L, Biemans R, Reniers B, Bosmans G, Trani D, Podesta M, Kollaard R, Rouschop KM, Theys J, Vooijs M, Pruschy M, Verhaegen F, Lambin P. High dose rate and flattening filter free irradiation can be safely implemented in clinical practice. Int J Radiat Biol 2015; 91:778-85. [DOI: 10.3109/09553002.2015.1068457] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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16
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Impact of flattening-filter-free radiation on the clonogenic survival of astrocytic cell lines. Strahlenther Onkol 2015; 191:590-6. [DOI: 10.1007/s00066-015-0823-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 01/28/2015] [Indexed: 11/25/2022]
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17
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Dahele M, van Sörnsen de Koste JR, van de Ven PM, Spoelstra F, Slotman B, Senan S. Parenchymal lung changes on computed tomography after stereotactic radiotherapy using high dose rate flattening filter free beams. Radiother Oncol 2015; 114:357-60. [DOI: 10.1016/j.radonc.2015.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 01/18/2015] [Accepted: 02/15/2015] [Indexed: 10/23/2022]
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18
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Stieb S, Lang S, Linsenmeier C, Graydon S, Riesterer O. Safety of high-dose-rate stereotactic body radiotherapy. Radiat Oncol 2015; 10:27. [PMID: 25614416 PMCID: PMC4313468 DOI: 10.1186/s13014-014-0317-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 12/21/2014] [Indexed: 12/25/2022] Open
Abstract
Background and purpose Flattening filter free (FFF) beams with high dose rate are increasingly used for stereotactic body radiotherapy (SBRT), because they substantially shorten beam-on time. The physical properties of these beams together with potentially unknown radiobiological effects might affect patient safety. Therefore here we analyzed the clinical outcome of our patients. Material and methods Between 3/2010 and 2/2014 84 patients with 100 lesions (lung 75, liver 10, adrenal 6, lymph nodes 5, others 4) were treated with SBRT using 6 MV FFF or 10 MV FFF beams at our institution. Clinical efficacy endpoints and toxicity were assessed by Kaplan-Meier analysis and CTCAE criteria version 4.0. Results Median follow-up was 11 months (range: 3–41). No severe acute toxicity was observed. There has been one case of severe late toxicity (1%), a grade 3 bile duct stricture that was possibly related to SBRT. For all patients, the 1-year local control rate, progression free survival and overall survival were 94%, 38% and 80% respectively, and for patients with lung lesions 94%, 48% and 83%, respectively. Conclusions No unexpected toxicity occurred. Toxicity and treatment efficacy are perfectly in range with studies investigating SBRT with flattened beams. The use of FFF beams at maximum dose rate for SBRT is time efficient and appears to be safe.
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Affiliation(s)
- Sonja Stieb
- Department of Radiation Oncology, University Hospital Zurich, Rämistrasse 100, 8091, Zurich, Switzerland.
| | - Stephanie Lang
- Department of Radiation Oncology, University Hospital Zurich, Rämistrasse 100, 8091, Zurich, Switzerland.
| | - Claudia Linsenmeier
- Department of Radiation Oncology, University Hospital Zurich, Rämistrasse 100, 8091, Zurich, Switzerland.
| | - Shaun Graydon
- Department of Radiation Oncology, University Hospital Zurich, Rämistrasse 100, 8091, Zurich, Switzerland.
| | - Oliver Riesterer
- Department of Radiation Oncology, University Hospital Zurich, Rämistrasse 100, 8091, Zurich, Switzerland.
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Hrbacek J, Lang S, Graydon SN, Klöck S, Riesterer O. Dosimetric comparison of flattened and unflattened beams for stereotactic ablative radiotherapy of stage I non-small cell lung cancer. Med Phys 2014; 41:031709. [DOI: 10.1118/1.4866231] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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20
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Boda-Heggemann J, Mai S, Fleckenstein J, Siebenlist K, Simeonova A, Ehmann M, Steil V, Wenz F, Lohr F, Stieler F. Flattening-filter-free intensity modulated breath-hold image-guided SABR (Stereotactic ABlative Radiotherapy) can be applied in a 15-min treatment slot. Radiother Oncol 2013; 109:505-9. [PMID: 24128805 DOI: 10.1016/j.radonc.2013.09.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 09/13/2013] [Accepted: 09/15/2013] [Indexed: 11/18/2022]
Abstract
Hypofractionated image-guided stereotactic ablative radiotherapy (igSABR) is effective in small lung/liver lesions. Computer-assisted breath-hold reduces intrafraction motion but, as every gating/triggering strategy, reduces the duty cycle, resulting in long fraction times if combined with intensity-modulated radiotherapy (IMRT). 10 MV flattening-filter-free IMRT reduces daily fraction duration to <10 min for single doses of 5-20 Gy.
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Affiliation(s)
- Judit Boda-Heggemann
- Department of Radiation Oncology, University Medical Center Mannheim, University of Heidelberg, Germany.
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