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Spohn SKB, Radicioni G, Eisfelder M, Zamboglou C, Baltas D, Grosu AL, Sachpazidis I. Predictors of radiation-induced late rectal toxicity in prostate cancer treatment: a volumetric and dosimetric analysis. Front Oncol 2024; 14:1371384. [PMID: 38737910 PMCID: PMC11082346 DOI: 10.3389/fonc.2024.1371384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 04/08/2024] [Indexed: 05/14/2024] Open
Abstract
Introduction Prostate cancer (PCa) is a prevalent malignancy in European men, often treated with radiotherapy (RT) for localized disease. While modern RT achieves high success rates, concerns about late gastrointestinal (GI) toxicities persist. This retrospective study aims to identify predictors for late GI toxicities following definitive conventionally fractionated external beam RT (EBRT) for PCa, specifically exploring the dose to the rectal wall. Materials and methods A cohort of 96 intermediate- to high-risk PCa patients underwent EBRT between 2008 and 2016. Rectum and rectum wall contours were delineated, and 3D dose matrices were extracted. Volumetric and dosimetric indices were computed, and statistical analyses were performed to identify predictors using the Mann-Whitney U-rank test, logistic regression, and recursive feature elimination. Results In our cohort, 15 out of 96 patients experienced grade II late proctitis. Our analysis reveals distinct optimal predictors for rectum and rectum wall (RW) structures varying with α/β values (3.0 and 2.3 Gy) across prescribed doses of 68 to 76 Gy. Despite variability, RW predictors demonstrate greater consistency, notably V68Gy[%] to V74Gy[%] for α/β 3.0 Gy, and V68Gy[%] to V70Gy[%] for α/β 2.3 Gy. The model with α/β 2.3 Gy, featuring RW volume receiving 70 Gy (V70Gy[%]), stands out with a BIC value of 62.92, indicating its superior predictive effectiveness. Finally, focusing solely on the rectum structure, the V74Gy[%] emerges the best predictor for α/β 3.0 Gy, with a BIC value of 66.73. Conclusion This investigation highlights the critical role of V70Gy[%] in the rectum wall as a robust predictor for grade II late gastrointestinal (GI) toxicity following external beam radiation therapy (EBRT) for prostate cancer (PCa). Furthermore, our findings suggest that focusing on the rectum wall specifically, rather than the entire rectum, may offer improved accuracy in assessing proctitis development. A V70Gy (in EQD2 with α/β 2.3 Gy) of ≤5% and if possible ≤1% for the rectal wall should be achieved to minimize the risk of late grade II proctitis.
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Affiliation(s)
- Simon K. B. Spohn
- Department of Radiation Oncology, Medical Centre – University of Freiburg, Faculty of Medicine, University of Freiburg, German Cancer Consortium (DKTK), Partner Site Freiburg, Freiburg, Germany
- Berta-Ottensein-Program, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Gianluca Radicioni
- Department of Radiation Oncology, Medical Centre – University of Freiburg, Faculty of Medicine, University of Freiburg, German Cancer Consortium (DKTK), Partner Site Freiburg, Freiburg, Germany
| | - Marcio Eisfelder
- Department of Radiation Oncology, Medical Centre – University of Freiburg, Faculty of Medicine, University of Freiburg, German Cancer Consortium (DKTK), Partner Site Freiburg, Freiburg, Germany
| | - Constantinos Zamboglou
- Department of Radiation Oncology, Medical Centre – University of Freiburg, Faculty of Medicine, University of Freiburg, German Cancer Consortium (DKTK), Partner Site Freiburg, Freiburg, Germany
- Department of Radiation Oncology, German Oncology Centre, European University Cyprus, Limassol, Cyprus
| | - Dimos Baltas
- Division of Medical Physics, Department of Radiation Oncology, Medical Centre - University of Freiburg, Faculty of Medicine, University of Freiburg, German Cancer Consortium (DKTK), Partner Site Freiburg, Freiburg, Germany
| | - Anca-Ligia Grosu
- Department of Radiation Oncology, Medical Centre – University of Freiburg, Faculty of Medicine, University of Freiburg, German Cancer Consortium (DKTK), Partner Site Freiburg, Freiburg, Germany
| | - Ilias Sachpazidis
- Division of Medical Physics, Department of Radiation Oncology, Medical Centre - University of Freiburg, Faculty of Medicine, University of Freiburg, German Cancer Consortium (DKTK), Partner Site Freiburg, Freiburg, Germany
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Quashie EE, Li XA, Prior P, Awan M, Schultz C, Tai A. Obtaining organ-specific radiobiological parameters from clinical data for radiation therapy planning of head and neck cancers. Phys Med Biol 2023; 68:245015. [PMID: 37903437 DOI: 10.1088/1361-6560/ad07f5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 10/30/2023] [Indexed: 11/01/2023]
Abstract
Objective.Different radiation therapy (RT) strategies, e.g. conventional fractionation RT (CFRT), hypofractionation RT (HFRT), stereotactic body RT (SBRT), adaptive RT, and re-irradiation are often used to treat head and neck (HN) cancers. Combining and/or comparing these strategies requires calculating biological effective dose (BED). The purpose of this study is to develop a practical process to estimate organ-specific radiobiologic model parameters that may be used for BED calculations in individualized RT planning for HN cancers.Approach.Clinical dose constraint data for CFRT, HFRT and SBRT for 5 organs at risk (OARs) namely spinal cord, brainstem, brachial plexus, optic pathway, and esophagus obtained from literature were analyzed. These clinical data correspond to a particular endpoint. The linear-quadratic (LQ) and linear-quadratic-linear (LQ-L) models were used to fit these clinical data and extract relevant model parameters (alpha/beta ratio, gamma/alpha,dTand BED) from the iso-effective curve. The dose constraints in terms of equivalent physical dose in 2 Gy-fraction (EQD2) were calculated using the obtained parameters.Main results.The LQ-L and LQ models fitted clinical data well from the CFRT to SBRT with the LQ-L representing a better fit for most of the OARs. The alpha/beta values for LQ-L (LQ) were found to be 2.72 (2.11) Gy, 0.55 (0.30) Gy, 2.82 (2.90) Gy, 6.57 (3.86) Gy, 5.38 (4.71) Gy, and the dose constraint EQD2 were 55.91 (54.90) Gy, 57.35 (56.79) Gy, 57.54 (56.35) Gy, 60.13 (59.72) Gy and 65.66 (64.50) Gy for spinal cord, optic pathway, brainstem, brachial plexus, and esophagus, respectively. Additional two LQ-L parametersdTwere 5.24 Gy, 5.09 Gy, 7.00 Gy, 5.23 Gy, and 6.16 Gy, and gamma/alpha were 7.91, 34.02, 8.67, 5.62 and 4.95.Significance.A practical process was developed to extract organ-specific radiobiological model parameters from clinical data. The obtained parameters can be used for biologically based radiation planning such as calculating dose constraints of different fractionation regimens.
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Affiliation(s)
- Edwin E Quashie
- Department of Radiation Oncology, Medical College of Wisconsin, WI 53226, United States of America
- Department of Radiation Oncology, Brown University School of Medicine, Providence, RI 02903, United States of America
- Department of Radiation Oncology, Rhode Island Hospital, Providence, RI 02903, United States of America
| | - X Allen Li
- Department of Radiation Oncology, Medical College of Wisconsin, WI 53226, United States of America
| | - Phillip Prior
- Department of Radiation Oncology, Medical College of Wisconsin, WI 53226, United States of America
| | - Musaddiq Awan
- Department of Radiation Oncology, Medical College of Wisconsin, WI 53226, United States of America
| | - Christopher Schultz
- Department of Radiation Oncology, Medical College of Wisconsin, WI 53226, United States of America
| | - An Tai
- Department of Radiation Oncology, Medical College of Wisconsin, WI 53226, United States of America
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Wolfe S, Diven MA, Marciscano AE, Zhou XK, Kishan AU, Steinberg ML, Miccio JA, Camilleri P, Nagar H. A randomized phase II trial of MR-guided prostate stereotactic body radiotherapy administered in 5 or 2 fractions for localized prostate cancer (FORT). BMC Cancer 2023; 23:923. [PMID: 37777738 PMCID: PMC10544147 DOI: 10.1186/s12885-023-11430-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 09/21/2023] [Indexed: 10/02/2023] Open
Abstract
BACKGROUND Ultra-hypofractionated regimens for definitive prostate cancer (PCa) radiotherapy are increasingly utilized due in part to promising safety and efficacy data complemented by greater patient convenience from a treatment course requiring fewer sessions. As such, stereotactic body radiation therapy (SBRT) is rapidly emerging as a standard definitive treatment option for patients with localized PCa. The commercially available magnetic resonance linear accelerator (MR-LINAC) integrates MR imaging with radiation delivery, providing several theoretical advantages compared to computed tomography (CT)-guided radiotherapy. MR-LINAC technology facilitates improved visualization of the prostate, real-time intrafraction tracking of prostate and organs-at-risk (OAR), and online adaptive planning to account for target movement and anatomical changes. These features enable reduced treatment volume margins and improved sparing of surrounding OAR. The theoretical advantages of MR-guided radiotherapy (MRgRT) have recently been shown to significantly reduce rates of acute grade ≥ 2 GU toxicities as reported in the prospective randomized phase III MIRAGE trial, which compared MR-LINAC vs CT-based 5 fraction SBRT in patients with localized PCa (Kishan et al. JAMA Oncol 9:365-373, 2023). Thus, MR-LINAC SBRT-utilizing potentially fewer treatments-is warranted and clinically relevant for men with low or intermediate risk PCa electing for radiotherapy as definitive treatment. METHODS/DESIGN A total of 136 men with treatment naïve low or intermediate risk PCa will be randomized in a 1:1 ratio to 5 or 2 fractions of MR-guided SBRT using permuted block randomization. Randomization is stratified by baseline Expanded PCa Index Composite (EPIC) bowel and urinary domain scores. Patients undergoing 5 fractions will receive 37.5 Gy to the prostate over 10-14 days and patients undergoing 2 fractions will receive 25 Gy to the prostate over 7-10 days. The co-primary endpoints are GI and GU toxicities as measured by change scores in the bowel and urinary EPIC domains, respectively. The change scores will be calculated as pre-treatment (baseline) score subtracted from the 2-year score. DISCUSSION FORT is an international, multi-institutional prospective randomized phase II trial evaluating whether MR-guided SBRT delivered in 2 fractions versus 5 fractions is non-inferior from a gastrointestinal (GI) and genitourinary (GU) toxicity standpoint at 2 years post-treatment in men with low or intermediate risk PCa. TRIAL REGISTRATION Clinicaltrials.gov identifier: NCT04984343 . Date of registration: July 30, 2021. PROTOCOL VERSION 4.0, Nov 8, 2022.
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Affiliation(s)
- Sydney Wolfe
- Department of Radiation Oncology, Weill Cornell Medicine/NewYork-Presbyterian, 525 East 68th Street, N-046, Box 169, New York, NY, 10065, USA
| | - Marshall A Diven
- Department of Radiation Oncology, Brooklyn Methodist Hospital/New York-Presbyterian, Brooklyn, NY, USA
| | - Ariel E Marciscano
- Department of Radiation Oncology, Weill Cornell Medicine/NewYork-Presbyterian, 525 East 68th Street, N-046, Box 169, New York, NY, 10065, USA
| | - Xi Kathy Zhou
- Division of Biostatistics, Department of Population Health Sciences, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
| | - A U Kishan
- Department of Radiation Oncology, University of California, Los Angeles, Los Angeles, CA, USA
| | - M L Steinberg
- Department of Radiation Oncology, University of California, Los Angeles, Los Angeles, CA, USA
| | | | | | - Himanshu Nagar
- Department of Radiation Oncology, Weill Cornell Medicine/NewYork-Presbyterian, 525 East 68th Street, N-046, Box 169, New York, NY, 10065, USA.
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Marciscano AE, Wolfe S, Zhou XK, Barbieri CE, Formenti SC, Hu JC, Molina AM, Nanus DM, Nauseef JT, Scherr DS, Sternberg CN, Tagawa ST, Nagar H. Randomized phase II trial of MRI-guided salvage radiotherapy for prostate cancer in 4 weeks versus 2 weeks (SHORTER). BMC Cancer 2023; 23:781. [PMID: 37608258 PMCID: PMC10463903 DOI: 10.1186/s12885-023-11278-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 08/08/2023] [Indexed: 08/24/2023] Open
Abstract
BACKGROUND Ultra-hypofractionated image-guided stereotactic body radiotherapy (SBRT) is increasingly used for definitive treatment of localized prostate cancer. Magnetic resonance imaging-guided radiotherapy (MRgRT) facilitates improved visualization, real-time tracking of targets and/or organs-at-risk (OAR), and capacity for adaptive planning which may translate to improved targeting and reduced toxicity to surrounding tissues. Given promising results from NRG-GU003 comparing conventional and moderate hypofractionation in the post-operative setting, there is growing interest in exploring ultra-hypofractionated post-operative regimens. It remains unclear whether this can be done safely and whether MRgRT may help mitigate potential toxicity. SHORTER (NCT04422132) is a phase II randomized trial prospectively evaluating whether salvage MRgRT delivered in 5 fractions versus 20 fractions is non-inferior with respect to gastrointestinal (GI) and genitourinary (GU) toxicities at 2-years post-treatment. METHODS A total of 136 patients will be randomized in a 1:1 ratio to salvage MRgRT in 5 fractions or 20 fractions using permuted block randomization. Patients will be stratified according to baseline Expanded Prostate Cancer Index Composite (EPIC) bowel and urinary domain scores as well as nodal treatment and androgen deprivation therapy (ADT). Patients undergoing 5 fractions will receive a total of 32.5 Gy over 2 weeks and patients undergoing 20 fractions will receive a total of 55 Gy over 4 weeks, with or without nodal coverage (25.5 Gy over 2 weeks and 42 Gy over 4 weeks) and ADT as per the investigator's discretion. The co-primary endpoints are change scores in the bowel and the urinary domains of the EPIC. The change scores will reflect the 2-year score minus the pre-treatment (baseline) score. The secondary endpoints include safety endpoints, including change in GI and GU symptoms at 3, 6, 12 and 60 months from completion of treatment, and efficacy endpoints, including time to progression, prostate cancer specific survival and overall survival. DISCUSSION The SHORTER trial is the first randomized phase II trial comparing toxicity of ultra-hypofractionated and hypofractionated MRgRT in the salvage setting. The primary hypothesis is that salvage MRgRT delivered in 5 fractions will not significantly increase GI and GU toxicities when compared to salvage MRgRT delivered in 20 fractions. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT04422132. Date of registration: June 9, 2020.
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Affiliation(s)
- Ariel E Marciscano
- Department of Radiation Oncology, Weill Cornell Medicine/NewYork-Presbyterian, 525 East 68th Street, Box 169, New York, NY, N-046, USA.
| | - Sydney Wolfe
- Department of Radiation Oncology, Weill Cornell Medicine/NewYork-Presbyterian, 525 East 68th Street, Box 169, New York, NY, N-046, USA
| | - Xi Kathy Zhou
- Department of Population Health Sciences, Division of Biostatistics, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
| | - Christopher E Barbieri
- Department of Urology, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
- Englander Institute for Precision Medicine, Weill Cornell Medicine/New York-Presbyterian, New York, NY, USA
| | - Silvia C Formenti
- Department of Radiation Oncology, Weill Cornell Medicine/NewYork-Presbyterian, 525 East 68th Street, Box 169, New York, NY, N-046, USA
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
| | - Jim C Hu
- Department of Urology, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
| | - Ana M Molina
- Englander Institute for Precision Medicine, Weill Cornell Medicine/New York-Presbyterian, New York, NY, USA
- Division of Hematology/Oncology, Department of Medicine, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
| | - David M Nanus
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
- Division of Hematology/Oncology, Department of Medicine, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
| | - Jones T Nauseef
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
- Englander Institute for Precision Medicine, Weill Cornell Medicine/New York-Presbyterian, New York, NY, USA
- Division of Hematology/Oncology, Department of Medicine, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
| | - Douglas S Scherr
- Department of Urology, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
| | - Cora N Sternberg
- Englander Institute for Precision Medicine, Weill Cornell Medicine/New York-Presbyterian, New York, NY, USA
- Division of Hematology/Oncology, Department of Medicine, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
| | - Scott T Tagawa
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
- Englander Institute for Precision Medicine, Weill Cornell Medicine/New York-Presbyterian, New York, NY, USA
- Division of Hematology/Oncology, Department of Medicine, Weill Cornell Medicine/NewYork-Presbyterian, New York, NY, USA
| | - Himanshu Nagar
- Department of Radiation Oncology, Weill Cornell Medicine/NewYork-Presbyterian, 525 East 68th Street, Box 169, New York, NY, N-046, USA
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Cicchetti A, Fiorino C, Ebert MA, Iacovacci J, Kennedy A, Joseph DJ, Denham JW, Vavassori V, Fellin G, Cozzarini C, Degli Esposti C, Gabriele P, Munoz F, Avuzzi B, Valdagni R, Rancati T. Validation of prediction models for radiation-induced late rectal bleeding: evidence from a large pooled population of prostate cancer patients. Radiother Oncol 2023; 183:109628. [PMID: 36934896 DOI: 10.1016/j.radonc.2023.109628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/03/2023] [Accepted: 03/10/2023] [Indexed: 03/19/2023]
Abstract
PURPOSE To validate published models for the risk estimate of grade≥1 (G1+), grade≥2 (G2+) and grade=3 (G3) late rectal bleeding (LRB) after radical radiotherapy for prostate cancer in a large pooled population from three prospective trials. MATERIALS AND METHODS The external validation population included patients from Europe, and Oceanian centres enrolled between 2003 and 2014. Patients received 3DCRT or IMRT at doses between 66-80 Gy. IMRT was administered with conventional or hypofractionated schemes (2.35-2.65 Gy/fr). LRB was prospectively scored using patient-reported questionnaires (LENT/SOMA scale) with a 3-year follow-up. All Normal Tissue Complication Probability (NTCP) models published until 2021 based on the Equivalent Uniform Dose (EUD) from the rectal Dose Volume Histogram (DVH) were considered for validation. Model performance in validation was evaluated through calibration and discrimination. RESULTS Sixteen NTCP models were tested on data from 1633 patients. G1+ LRB was scored in 465 patients (28.5%), G2+ in 255 patients (15.6%) and G3 in 112 patients (6.8%). The best performances for G2+ and G3 LRB highlighted the importance of the medium-high doses to the rectum (volume parameters n=0.24 and n=0.18, respectively). Good performance was seen for models of severe LRB. Moreover, a multivariate model with two clinical factors found the best calibration slope. CONCLUSION Five published NTCP models developed on non-contemporary cohorts were able to predict a relative increase in the toxicity response in a more recent validation population. Compared to QUANTEC findings, dosimetric results pointed toward mid-high doses of rectal DVH. The external validation cohort confirmed abdominal surgery and cardiovascular diseases as risk factors.
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Affiliation(s)
- Alessandro Cicchetti
- Prostate Cancer Program, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy.
| | - Claudio Fiorino
- Medical Physics, San Raffaele Scientific Institute, Milan, Italy
| | - Martin A Ebert
- University of Western Australia, Perth, Western Australia; Radiation Oncology, Sir Charles Gairdner Hospital, Perth, Western Australia; 5D Clinics, Claremont, Western Australia
| | - Jacopo Iacovacci
- Prostate Cancer Program, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Angel Kennedy
- Radiation Oncology, Sir Charles Gairdner Hospital, Perth, Western Australia
| | - David J Joseph
- University of Western Australia, Perth, Western Australia; 5D Clinics, Claremont, Western Australia; GenesisCare, Perth, Western Australia
| | - James W Denham
- School of Medicine and Public Health, University of Newcastle, New South Wales, Australia
| | | | - Gianni Fellin
- Radiation Oncology, Ospedale Santa Chiara, Trento, Italy
| | - Cesare Cozzarini
- Radiation Oncology, San Raffaele Scientific Institute, Milan, Italy
| | | | - Pietro Gabriele
- Radiation Oncology, Istituto di Candiolo- Fondazione del Piemonte per l'Oncologia IRCCS, Torino, Italy
| | - Fernando Munoz
- Radiation Oncology, Azienda Ospedaliera di Aosta, Aosta, Italy
| | - Barbara Avuzzi
- Radiation Oncology 1, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Riccardo Valdagni
- Prostate Cancer Program, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy; Radiation Oncology 1, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy; Oncology and Hemato-Oncology, Università degli Studi,Milano, Italy
| | - Tiziana Rancati
- Prostate Cancer Program, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
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Dennstädt F, Medová M, Putora PM, Glatzer M. Parameters of the Lyman Model for Calculation of Normal-Tissue Complication Probability: A Systematic Literature Review. Int J Radiat Oncol Biol Phys 2023; 115:696-706. [PMID: 36029911 DOI: 10.1016/j.ijrobp.2022.08.039] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 08/10/2022] [Accepted: 08/13/2022] [Indexed: 02/04/2023]
Abstract
PURPOSE The Lyman model is one of the most used radiobiological models for calculation of normal-tissue complication probability (NTCP). Since its introduction in 1985, many authors have published parameter values for the model based on clinical data of different radiotherapeutic situations. This study attempted to collect the entirety of radiobiological parameter sets published to date and provide an overview of the data basis for different variations of the model. Furthermore, it sought to compare the parameter values and calculated NTCPs for selected endpoints with sufficient data available. METHODS AND MATERIALS A systematic literature analysis was performed, searching for publications that provided parameters for the different variations of the Lyman model in the Medline database using PubMed. Parameter sets were grouped into 13 toxicity-related endpoint groups. For 3 selected endpoint groups (≤25% reduction of saliva 12 months after irradiation of the parotid, symptomatic pneumonitis after irradiation of the lung, and bleeding of grade 2 or less after irradiation of the rectum), parameter values were compared and differences in calculated NTCP values were analyzed. RESULTS A total of 509 parameter sets from 130 publications were identified. Considerable heterogeneities were detected regarding the number of parameters available for different radio-oncological situations. Furthermore, for the 3 selected endpoints, large differences in published parameter values were found. These translated into great variations of calculated NTCPs, with maximum ranges of 35.2% to 93.4% for the saliva endpoint, of 39.4% to 90.4% for the pneumonitis endpoint, and of 5.4% to 99.3% for the rectal bleeding endpoint. CONCLUSIONS The detected heterogeneity of the data as well as the large variations of published radiobiological parameters underline the necessity for careful interpretation when using such parameters for NTCP calculations. Appropriate selection of parameters and validation of values are essential when using the Lyman model.
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Affiliation(s)
- Fabio Dennstädt
- Department of Radiation Oncology, Kantonsspital St. Gallen, St. Gallen, Switzerland.
| | - Michaela Medová
- Department of Radiation Oncology, University of Bern, Bern, Switzerland; Department for BioMedical Research, Inselspital Bern, Bern, Switzerland
| | - Paul Martin Putora
- Department of Radiation Oncology, Kantonsspital St. Gallen, St. Gallen, Switzerland; Department of Radiation Oncology, University of Bern, Bern, Switzerland
| | - Markus Glatzer
- Department of Radiation Oncology, Kantonsspital St. Gallen, St. Gallen, Switzerland
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Brand DH, Brüningk SC, Wilkins A, Naismith O, Gao A, Syndikus I, Dearnaley DP, van As N, Hall E, Gulliford S, Tree AC. The Fraction Size Sensitivity of Late Genitourinary Toxicity: Analysis of Alpha/Beta (α/β) Ratios in the CHHiP Trial. Int J Radiat Oncol Biol Phys 2023; 115:327-336. [PMID: 35985457 DOI: 10.1016/j.ijrobp.2022.08.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 08/04/2022] [Accepted: 08/06/2022] [Indexed: 01/14/2023]
Abstract
PURPOSE Moderately hypofractionated external beam intensity modulated radiation therapy (RT) for prostate cancer is now standard-of-care. Normal tissue toxicity responses to fraction size alteration are nonlinear: the linear-quadratic model is a widely used framework accounting for this, through the α/β ratio. Few α/β ratio estimates exist for human late genitourinary endpoints; here we provide estimates derived from a hypofractionation trial. METHODS AND MATERIALS The CHHiP trial randomized 3216 men with localized prostate cancer 1:1:1 between conventionally fractionated intensity modulated RT (74 Gy/37 fractions (Fr)) and 2 moderately hypofractionated regimens (60 Gy/20 Fr and 57 Gy/19 Fr). RT plan and suitable follow-up assessment was available for 2206 men. Three prospectively assessed clinician-reported toxicity scales were amalgamated for common genitourinary endpoints: dysuria, hematuria, incontinence, reduced flow/stricture, and urine frequency. Per endpoint, only patients with baseline zero toxicity were included. Three models for endpoint grade ≥1 (G1+) and G2+ toxicity were fitted: Lyman Kutcher-Burman (LKB) without equivalent dose in 2 Gy/Fr (EQD2) correction [LKB-NoEQD2]; LKB with EQD2-correction [LKB-EQD2]; LKB-EQD2 with dose-modifying-factor (DMF) inclusion [LKB-EQD2-DMF]. DMFs were age, diabetes, hypertension, pelvic surgery, prior transurethral resection of prostate (TURP), overall treatment time and acute genitourinary toxicity (G2+). Bootstrapping generated 95% confidence intervals and unbiased performance estimates. Models were compared by likelihood ratio test. RESULTS The LKB-EQD2 model significantly improved performance over LKB-NoEQD2 for just 3 endpoints: dysuria G1+ (α/β = 2.0 Gy; 95% confidence interval [CI], 1.2-3.2 Gy), hematuria G1+ (α/β = 0.9 Gy; 95% CI, 0.1-2.2 Gy) and hematuria G2+ (α/β = 0.6 Gy; 95% CI, 0.1-1.7 Gy). For these 3 endpoints, further incorporation of 2 DMFs improved on LKB-EQD2: acute genitourinary toxicity and prior TURP (hematuria G1+ only), but α/β ratio estimates remained stable. CONCLUSIONS Inclusion of EQD2-correction significantly improved model fitting for dysuria and hematuria endpoints, where fitted α/β ratio estimates were low: 0.6 to 2 Gy. This suggests therapeutic gain for clinician-reported GU toxicity, through hypofractionation, might be lower than expected by typical late α/β ratio assumptions of 3 to 5 Gy.
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Affiliation(s)
- Douglas H Brand
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom; Urology Unit, Royal Marsden NHS Foundation Trust, London, United Kingdom; Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom.
| | - Sarah C Brüningk
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland; Swiss Institute for Bioinformatics (SIB), Lausanne, Switzerland
| | - Anna Wilkins
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom; Urology Unit, Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Olivia Naismith
- Radiotherapy Trials QA Group (RTTQA), Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Annie Gao
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom; Urology Unit, Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Isabel Syndikus
- Radiotherapy Department, Clatterbridge Cancer Centre, Liverpool, United Kingdom
| | - David P Dearnaley
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom; Urology Unit, Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Nicholas van As
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom; Urology Unit, Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Emma Hall
- Clinical Trials and Statistics Unit, The Institute of Cancer Research, London, United Kingdom
| | - Sarah Gulliford
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom; Department of Radiotherapy Physics, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Alison C Tree
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom; Urology Unit, Royal Marsden NHS Foundation Trust, London, United Kingdom
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Tree AC, Ostler P, van der Voet H, Chu W, Loblaw A, Ford D, Tolan S, Jain S, Martin A, Staffurth J, Armstrong J, Camilleri P, Kancherla K, Frew J, Chan A, Dayes IS, Duffton A, Brand DH, Henderson D, Morrison K, Brown S, Pugh J, Burnett S, Mahmud M, Hinder V, Naismith O, Hall E, van As N. Intensity-modulated radiotherapy versus stereotactic body radiotherapy for prostate cancer (PACE-B): 2-year toxicity results from an open-label, randomised, phase 3, non-inferiority trial. Lancet Oncol 2022; 23:1308-1320. [PMID: 36113498 DOI: 10.1016/s1470-2045(22)00517-4] [Citation(s) in RCA: 103] [Impact Index Per Article: 51.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 08/10/2022] [Accepted: 08/11/2022] [Indexed: 10/14/2022]
Abstract
BACKGROUND Localised prostate cancer is commonly treated with external beam radiotherapy and moderate hypofractionation is non-inferior to longer schedules. Stereotactic body radiotherapy (SBRT) allows shorter treatment courses without impacting acute toxicity. We report 2-year toxicity findings from PACE-B, a randomised trial of conventionally fractionated or moderately hypofractionated radiotherapy versus SBRT. METHODS PACE is an open-label, multicohort, randomised, controlled, phase 3 trial conducted at 35 hospitals in the UK, Ireland, and Canada. In PACE-B, men aged 18 years and older with a WHO performance status 0-2 and low-risk or intermediate-risk histologically-confirmed prostate adenocarcinoma (Gleason 4 + 3 excluded) were randomly allocated (1:1) by computerised central randomisation with permuted blocks (size four and six), stratified by centre and risk group to control radiotherapy (CRT; 78 Gy in 39 fractions over 7·8 weeks or, following protocol amendment on March 24, 2016, 62 Gy in 20 fractions over 4 weeks) or SBRT (36·25 Gy in five fractions over 1-2 weeks). Androgen deprivation was not permitted. Co-primary outcomes for this toxicity analysis were Radiation Therapy Oncology Group (RTOG) grade 2 or worse gastrointestinal and genitourinary toxicity at 24 months after radiotherapy. Analysis was by treatment received and included all patients with at least one fraction of study treatment assessed for late toxicity. Recruitment is complete. Follow-up for oncological outcomes continues. The trial is registered with ClinicalTrials.gov, NCT01584258. FINDINGS We enrolled and randomly assigned 874 men between Aug 7, 2012, and Jan 4, 2018 (441 to CRT and 433 to SBRT). In this analysis, 430 patients were analysed in the CRT group and 414 in the SBRT group; a total of 844 (97%) of 874 randomly assigned patients. At 24 months, RTOG grade 2 or worse genitourinary toxicity was seen in eight (2%) of 381 participants assigned to CRT and 13 (3%) of 384 participants assigned to SBRT (absolute difference 1·3% [95% CI -1·3 to 4·0]; p=0·39); RTOG grade 2 or worse gastrointestinal toxicity was seen in 11 (3%) of 382 participants in the CRT group versus six (2%) of 384 participants in the SBRT group (absolute difference -1·3% [95% CI -3·9 to 1·1]; p=0·32). No serious adverse events (defined as RTOG grade 4 or worse) or treatment-related deaths were reported within the analysis timeframe. INTERPRETATION In the PACE-B trial, 2-year RTOG toxicity rates were similar for five fraction SBRT and conventional schedules of radiotherapy. Prostate SBRT was found to be safe and associated with low rates of side-effects. Biochemical outcomes are awaited. FUNDING Accuray.
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Affiliation(s)
- Alison C Tree
- The Royal Marsden Hospital, London, UK; The Institute of Cancer Research, London, UK.
| | | | | | - William Chu
- Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Andrew Loblaw
- Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Daniel Ford
- University Hospitals Birmingham, Birmingham, UK
| | - Shaun Tolan
- The Clatterbridge Cancer Centre, Liverpool, UK
| | | | - Alexander Martin
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | | | - John Armstrong
- Cancer Trials Ireland, Dublin, Ireland; St Luke's Radiation Oncology Network, St Lukes Hospital, Dublin, Ireland
| | | | | | | | - Andrew Chan
- University Hospitals Coventry & Warwickshire, Coventry, UK
| | - Ian S Dayes
- Department of Oncology, McMaster University, Hamilton, ON, Canada
| | | | - Douglas H Brand
- The Royal Marsden Hospital, London, UK; The Institute of Cancer Research, London, UK
| | | | - Kirsty Morrison
- The Royal Marsden Hospital, London, UK; The Institute of Cancer Research, London, UK
| | | | - Julia Pugh
- The Institute of Cancer Research, London, UK
| | | | | | | | - Olivia Naismith
- The Royal Marsden Hospital, London, UK; Radiotherapy Trials QA Group, London, UK
| | - Emma Hall
- The Institute of Cancer Research, London, UK
| | - Nicholas van As
- The Royal Marsden Hospital, London, UK; The Institute of Cancer Research, London, UK
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Brand DH, Tree AC. Fractionation Choice for Elective Lymph Node Radiation Therapy in Prostate Cancer: Slightly More to CHIRP About. Int J Radiat Oncol Biol Phys 2022; 114:108-110. [PMID: 35843786 DOI: 10.1016/j.ijrobp.2022.05.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 05/24/2022] [Indexed: 10/17/2022]
Affiliation(s)
- Douglas H Brand
- Department of Medical Physics and Bioengineering, University College London, London, United Kingdom; Department of Clinical Oncology, University College London Hospitals, London, United Kingdom; Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom
| | - Alison C Tree
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom; Urology Unit, Royal Marsden NHS Foundation Trust, London, United Kingdom.
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Brand DH, Kirby AM, Yarnold JR, Somaiah N. How Low Can You Go? The Radiobiology of Hypofractionation. Clin Oncol (R Coll Radiol) 2022; 34:280-287. [PMID: 35260319 DOI: 10.1016/j.clon.2022.02.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Revised: 01/25/2022] [Accepted: 02/11/2022] [Indexed: 12/25/2022]
Abstract
Hypofractionated radical radiotherapy is now an accepted standard of care for tumour sites such as prostate and breast cancer. Much research effort is being directed towards more profoundly hypofractionated (ultrahypofractionated) schedules, with some reaching UK standard of care (e.g. adjuvant breast). Hypofractionation exerts varying influences on each of the major clinical end points of radiotherapy studies: acute toxicity, late toxicity and local control. This review will discuss these effects from the viewpoint of the traditional 5 Rs of radiobiology, before considering non-canonical radiobiological effects that may be relevant to ultrahypofractionated radiotherapy. The principles outlined here may assist the reader in their interpretation of the wealth of clinical data presented in the tumour site-specific articles in this special issue.
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Affiliation(s)
- D H Brand
- The Institute of Cancer Research, London, UK
| | - A M Kirby
- The Institute of Cancer Research, London, UK; The Royal Marsden NHS Foundation Trust, London, UK
| | - J R Yarnold
- The Institute of Cancer Research, London, UK; The Royal Marsden NHS Foundation Trust, London, UK
| | - N Somaiah
- The Institute of Cancer Research, London, UK; The Royal Marsden NHS Foundation Trust, London, UK.
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Androulakis I, Mestrom RMC, Christianen MEMC, Kolkman-Deurloo IK, van Rhoon GC. A Novel Framework for the Optimization of Simultaneous ThermoBrachyTherapy. Cancers (Basel) 2022; 14. [PMID: 35326574 DOI: 10.3390/cancers14061425] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 03/04/2022] [Accepted: 03/10/2022] [Indexed: 12/15/2022] Open
Abstract
In high-dose-rate brachytherapy (HDR-BT) for prostate cancer treatment, interstitial hyperthermia (IHT) is applied to sensitize the tumor to the radiation (RT) dose, aiming at a more efficient treatment. Simultaneous application of HDR-BT and IHT is anticipated to provide maximum radiosensitization of the tumor. With this rationale, the ThermoBrachyTherapy applicators have been designed and developed, enabling simultaneous irradiation and heating. In this research, we present a method to optimize the three-dimensional temperature distribution for simultaneous HDR-BT and IHT based on the resulting equivalent physical dose (EQDphys) of the combined treatment. First, the temperature resulting from each electrode is precomputed. Then, for a given set of electrode settings and a precomputed radiation dose, the EQDphys is calculated based on the temperature-dependent linear-quadratic model. Finally, the optimum set of electrode settings is found through an optimization algorithm. The method is applied on implant geometries and anatomical data of 10 previously irradiated patients, using reported thermoradiobiological parameters and physical doses. We found that an equal equivalent dose coverage of the target can be achieved with a physical RT dose reduction of 20% together with a significantly lower EQDphys to the organs at risk (p-value < 0.001), even in the least favorable scenarios. As a result, simultaneous ThermoBrachyTherapy could lead to a relevant therapeutic benefit for patients with prostate cancer.
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Koukourakis MI, Kavazis C, Giagtzidis A, Mamalis P, Tsaroucha A, Botaitis S, Giatromanolaki A, Pitiakoudis M. Postoperative hypofractionated-accelerated radiotherapy (HypoAR) for locally advanced rectal cancer. Jpn J Clin Oncol 2022; 52:493-498. [PMID: 35079795 DOI: 10.1093/jjco/hyab216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 12/31/2021] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND despite the advances in preoperative hypofractionated-accelerated radiotherapy for patients with locally advanced rectal cancer, postoperative radiotherapy delivered with standard fractionation (46-50 Gy in 5 weeks) remains a standard adjuvant schedule. The role of hypofractionated-accelerated radiotherapy in a postoperative setting remains largely unexplored. METHODS eighty-eight patients with rectal cancer infiltrating the rectal wall and/or having metastasis to the perirectal lymph nodes were treated with surgery followed by adjuvant chemotherapy and, subsequently, with hypofractionated-accelerated radiotherapy. Ten fractions of 3.4 Gy were delivered to the pelvis for 10 consecutive fractions, within 12 days. The follow-up of patients alive at the time of analysis ranges from 12-120 months (median 48). RESULTS mild abdominal discomfort and diarrhoea were frequent, but medical medication was demanded in 14/88 (15.9%) of patients. The incidence of late toxicities was low; 4/88 (3.5%) patients complained for intermittent intestinal urgency. Locoregional recurrence occurred in 8/88 patients (9%). The 5-year locoregional relapse-free survival was achieved in 89.7% of patients, and this dropped to 84% in node-positive patients (P = 0.45). The 5-year disease-specific overall survival was 72.4%. Nodal involvement showed a trend to negatively affect prognosis (5-year overall survival 68.2 vs. 79.6%; P = 0.23). CONCLUSION postoperative hypofractionated-accelerated radiotherapy has minimal early and late toxicity. The locoregional control and disease-specific survival rates are similar to the expected from conventional postoperative chemoradiotherapy. The 2.5-fold decrease of radiotherapy treatment time, reduction of waiting lists and the lower overall cost of radiotherapy are additional benefits associated with hypofractionated-accelerated radiotherapy.
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Affiliation(s)
| | | | | | | | | | | | - Alexandra Giatromanolaki
- Department of Pathology, Democritus University of Thrace, University Hospital of Alexandroupolis, Alexandroupolis, Greece
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De Roover R, Crijns W, Poels K, Dewit B, Draulans C, Haustermans K, Depuydt T. Automated treatment planning of prostate stereotactic body radiotherapy with focal boosting on a fast-rotating O-ring linac: Plan quality comparison with C-arm linacs. J Appl Clin Med Phys 2021; 22:59-72. [PMID: 34318996 PMCID: PMC8425873 DOI: 10.1002/acm2.13345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 05/26/2021] [Indexed: 11/14/2022] Open
Abstract
Purpose The integration of auto‐segmentation and automated treatment planning methods on a fast‐rotating O‐ring linac may improve the time efficiency of online adaptive radiotherapy workflows. This study investigates whether automated treatment planning of prostate SBRT with focal boosting on the O‐ring linac could generate plans that are of similar quality as those obtained through manual planning on clinical C‐arm linacs. Methods For 20 men with prostate cancer, reference treatment plans were generated on a TrueBeam STx C‐arm linac with HD120 MLC and a TrueBeam C‐arm linac with Millennium 120 MLC using 6 MV flattened dual arc VMAT. Manual planning on the Halcyon fast‐rotating O‐ring linac was performed using 6 MV FFF dual arc VMAT (HA2‐DL10) and triple arc VMAT (HA3‐DL10) to investigate the performance of the dual‐layer MLC system. Automated planning was performed for triple arc VMAT on the Halcyon linac (ET3‐DL10) using the automated planning algorithms of Ethos Treatment Planning. The prescribed dose was 35 Gy to the prostate and 30 Gy to the seminal vesicles in five fractions. The iso‐toxic focal boost to the intraprostatic tumor nodule(s) was aimed to receive up to 50 Gy. Plan deliverability was verified using portal image dosimetry measurements. Results Compared to the C‐arm linacs, ET3‐DL10 shows increased seminal vesicles PTV coverage (D99%) and reduced high‐dose spillage to the bladder (V37Gy) and urethra (D0.035cc) but this came at the cost of increased high‐dose spillage to the rectum (V38Gy) and a higher intermediate dose spillage (D2cm). No statistically significant differences were found when benchmarking HA2‐DL10 and HA3‐DL10 with the C‐arm linacs. All plans passed the patient‐specific QA tolerance limit. Conclusions Automated planning of prostate SBRT with focal boosting on the fast‐rotating O‐ring linac is feasible and achieves similar plan quality as those obtained on clinical C‐arm linacs using manual planning.
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Affiliation(s)
- Robin De Roover
- Department of Radiation Oncology, University Hospitals Leuven, Leuven, Belgium.,Department of Oncology, KU Leuven, Leuven, Belgium
| | - Wouter Crijns
- Department of Radiation Oncology, University Hospitals Leuven, Leuven, Belgium.,Department of Oncology, KU Leuven, Leuven, Belgium
| | - Kenneth Poels
- Department of Radiation Oncology, University Hospitals Leuven, Leuven, Belgium.,Department of Oncology, KU Leuven, Leuven, Belgium
| | - Bertrand Dewit
- Department of Radiation Oncology, University Hospitals Leuven, Leuven, Belgium.,Department of Oncology, KU Leuven, Leuven, Belgium
| | - Cédric Draulans
- Department of Radiation Oncology, University Hospitals Leuven, Leuven, Belgium.,Department of Oncology, KU Leuven, Leuven, Belgium
| | - Karin Haustermans
- Department of Radiation Oncology, University Hospitals Leuven, Leuven, Belgium.,Department of Oncology, KU Leuven, Leuven, Belgium
| | - Tom Depuydt
- Department of Radiation Oncology, University Hospitals Leuven, Leuven, Belgium.,Department of Oncology, KU Leuven, Leuven, Belgium
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