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Tobias Böhlen T, Psoroulas S, Aylward JD, Beddar S, Douralis A, Delpon G, Garibaldi C, Gasparini A, Schüler E, Stephan F, Moeckli R, Subiel A. Recording and reporting of ultra-high dose rate "FLASH" delivery for preclinical and clinical settings. Radiother Oncol 2024; 200:110507. [PMID: 39245070 DOI: 10.1016/j.radonc.2024.110507] [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: 01/26/2024] [Revised: 08/08/2024] [Accepted: 08/19/2024] [Indexed: 09/10/2024]
Abstract
Treatments at ultra-high dose rate (UHDR) have the potential to improve the therapeutic index of radiation therapy (RT) by sparing normal tissues compared to conventional dose rate irradiations. Insufficient and inconsistent reporting in physics and dosimetry of preclinical and translational studies may have contributed to a reproducibility crisis of radiobiological data in the field. Consequently, the development of a common terminology, as well as common recording, reporting, dosimetry, and metrology standards is required. In the context of UHDR irradiations, the temporal dose delivery parameters are of importance, and under-reporting of these parameters is also a concern.This work proposes a standardization of terminology, recording, and reporting to enhance comparability of both preclinical and clinical UHDR studies and and to allow retrospective analyses to aid the understanding of the conditions which give rise to the FLASH effect.
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Affiliation(s)
- Till Tobias Böhlen
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Serena Psoroulas
- Center for Proton Therapy, Paul Scherrer Institute, Villigen PSI, Switzerland; Klinik für Radio-Onkologie, UniversitätsSpital Zürich, Switzerland
| | - Jack D Aylward
- Division of Cancer Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK; Christie Medical Physics and Engineering, The Christie NHS Foundation Trust, Manchester, UK; Medical Physics, School of Applied Sciences, University of the West of England, Bristol, UK
| | - Sam Beddar
- The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | | | - Grégory Delpon
- Institut de Cancérologie de l'Ouest, Medical Physics Department, Saint-Herblain, France; Nantes Université, IMT Atlantique, CNRS/IN2P3, SUBATECH, Nantes, France
| | - Cristina Garibaldi
- IEO, Unit of Radiation Research, European Institute of Oncology IRCCS, 20141 Milan, Italy
| | - Alessia Gasparini
- CORE, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium; Medical Physics Department, Iridium Netwerk, Wilrijk, Belgium
| | - Emil Schüler
- The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Frank Stephan
- Deutsches Elektronen-Synchrotron DESY, Platanenallee 6, 15738 Zeuthen, Germany
| | - Raphaël Moeckli
- Institute of Radiation Physics, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland.
| | - Anna Subiel
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, UK; University College London, Gower Street, London WC1E 6BT, UK.
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2
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Esplen N, Egoriti L, Planche T, Rädel S, Koay HW, Humphries B, Ren X, Ford N, Hoehr C, Gottberg A, Bazalova-Carter M. Dosimetric characterization of a novel UHDR megavoltage X-ray source for FLASH radiobiological experiments. Sci Rep 2024; 14:822. [PMID: 38191885 PMCID: PMC10774358 DOI: 10.1038/s41598-023-50412-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Accepted: 12/19/2023] [Indexed: 01/10/2024] Open
Abstract
A first irradiation platform capable of delivering 10 MV X-ray beams at ultra-high dose rates (UHDR) has been developed and characterized for FLASH radiobiological research at TRIUMF. Delivery of both UHDR (FLASH mode) and low dose-rate conventional (CONV mode) irradiations was demonstrated using a common source and experimental setup. Dose rates were calculated using film dosimetry and a non-intercepting beam monitoring device; mean values for a 100 μA pulse (peak) current were nominally 82.6 and 4.40 × 10-2 Gy/s for UHDR and CONV modes, respectively. The field size for which > 40 Gy/s could be achieved exceeded 1 cm down to a depth of 4.1 cm, suitable for total lung irradiations in mouse models. The calculated delivery metrics were used to inform subsequent pre-clinical treatments. Four groups of 6 healthy male C57Bl/6J mice were treated using thoracic irradiations to target doses of either 15 or 30 Gy using both FLASH and CONV modes. Administration of UHDR X-ray irradiation to healthy mouse models was demonstrated for the first time at the clinically-relevant beam energy of 10 MV.
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Affiliation(s)
- Nolan Esplen
- Physics and Astronomy, University of Victoria, Victoria, V8P 5C2, Canada
| | - Luca Egoriti
- TRIUMF, Vancouver, V6T 2A3, Canada
- Chemistry, University of British Columbia, Vancouver, V6T 1Z1, Canada
| | | | | | | | | | - Xi Ren
- Physics and Astronomy, University of British Columbia, Vancouver, V6T 1Z1, Canada
| | - Nancy Ford
- Physics and Astronomy, University of British Columbia, Vancouver, V6T 1Z1, Canada
- Oral Biological and Medical Sciences, University of British Columbia, Vancouver, V6T 1Z1, Canada
| | - Cornelia Hoehr
- Physics and Astronomy, University of Victoria, Victoria, V8P 5C2, Canada
- TRIUMF, Vancouver, V6T 2A3, Canada
| | - Alexander Gottberg
- Physics and Astronomy, University of Victoria, Victoria, V8P 5C2, Canada
- TRIUMF, Vancouver, V6T 2A3, Canada
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3
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Tan Y, Zhou S, Haefner J, Chen Q, Mazur TR, Darafsheh A, Zhang T. Simulation study of a novel small animal FLASH irradiator (SAFI) with integrated inverse-geometry CT based on circularly distributed kV X-ray sources. Sci Rep 2023; 13:20181. [PMID: 37978269 PMCID: PMC10656503 DOI: 10.1038/s41598-023-47421-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 11/14/2023] [Indexed: 11/19/2023] Open
Abstract
Ultra-high dose rate (UHDR) radiotherapy (RT) or FLASH-RT can potentially reduce normal tissue toxicity. A small animal irradiator that can deliver FLASH-RT treatments similar to clinical RT treatments is needed for pre-clinical studies of FLASH-RT. We designed and simulated a novel small animal FLASH irradiator (SAFI) based on distributed x-ray source technology. The SAFI system comprises a distributed x-ray source with 51 focal spots equally distributed on a 20 cm diameter ring, which are used for both FLASH-RT and onboard micro-CT imaging. Monte Carlo simulation was performed to estimate the dosimetric characteristics of the SAFI treatment beams. The maximum dose rate, which is limited by the power density of the tungsten target, was estimated based on finite-element analysis (FEA). The maximum DC electron beam current density is 2.6 mA/mm2, limited by the tungsten target's linear focal spot power density. At 160 kVp, 51 focal spots, each with a dimension of [Formula: see text] mm2 and 10° anode angle, can produce up to 120 Gy/s maximum DC irradiation at the center of a cylindrical water phantom. We further demonstrate forward and inverse FLASH-RT planning, as well as inverse-geometry micro-CT with circular source array imaging via numerical simulations.
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Affiliation(s)
- Yuewen Tan
- Department of Radiation Oncology, Washington University School of Medicine in St. Louis, St. Louis, MO, 63110, USA
- Department of Physics, Washington University in St. Louis, St. Louis, MO, 63130, USA
- Center for Radiological Research, Columbia University, New York, NY, 10032, USA
| | - Shuang Zhou
- Department of Radiation Oncology, Washington University School of Medicine in St. Louis, St. Louis, MO, 63110, USA
| | - Jonathan Haefner
- Department of Radiation Oncology, Washington University School of Medicine in St. Louis, St. Louis, MO, 63110, USA
| | - Qinghao Chen
- Department of Radiation Oncology, Washington University School of Medicine in St. Louis, St. Louis, MO, 63110, USA
| | - Thomas R Mazur
- Department of Radiation Oncology, Washington University School of Medicine in St. Louis, St. Louis, MO, 63110, USA
| | - Arash Darafsheh
- Department of Radiation Oncology, Washington University School of Medicine in St. Louis, St. Louis, MO, 63110, USA
| | - Tiezhi Zhang
- Department of Radiation Oncology, Washington University School of Medicine in St. Louis, St. Louis, MO, 63110, USA.
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4
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Zou W, Zhang R, Schüler E, Taylor PA, Mascia AE, Diffenderfer ES, Zhao T, Ayan AS, Sharma M, Yu SJ, Lu W, Bosch WR, Tsien C, Surucu M, Pollard-Larkin JM, Schuemann J, Moros EG, Bazalova-Carter M, Gladstone DJ, Li H, Simone CB, Petersson K, Kry SF, Maity A, Loo BW, Dong L, Maxim PG, Xiao Y, Buchsbaum JC. Framework for Quality Assurance of Ultrahigh Dose Rate Clinical Trials Investigating FLASH Effects and Current Technology Gaps. Int J Radiat Oncol Biol Phys 2023; 116:1202-1217. [PMID: 37121362 PMCID: PMC10526970 DOI: 10.1016/j.ijrobp.2023.04.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 03/28/2023] [Accepted: 04/17/2023] [Indexed: 05/02/2023]
Abstract
FLASH radiation therapy (FLASH-RT), delivered with ultrahigh dose rate (UHDR), may allow patients to be treated with less normal tissue toxicity for a given tumor dose compared with currently used conventional dose rate. Clinical trials are being carried out and are needed to test whether this improved therapeutic ratio can be achieved clinically. During the clinical trials, quality assurance and credentialing of equipment and participating sites, particularly pertaining to UHDR-specific aspects, will be crucial for the validity of the outcomes of such trials. This report represents an initial framework proposed by the NRG Oncology Center for Innovation in Radiation Oncology FLASH working group on quality assurance of potential UHDR clinical trials and reviews current technology gaps to overcome. An important but separate consideration is the appropriate design of trials to most effectively answer clinical and scientific questions about FLASH. This paper begins with an overview of UHDR RT delivery methods. UHDR beam delivery parameters are then covered, with a focus on electron and proton modalities. The definition and control of safe UHDR beam delivery and current and needed dosimetry technologies are reviewed and discussed. System and site credentialing for large, multi-institution trials are reviewed. Quality assurance is then discussed, and new requirements are presented for treatment system standard analysis, patient positioning, and treatment planning. The tables and figures in this paper are meant to serve as reference points as we move toward FLASH-RT clinical trial performance. Some major questions regarding FLASH-RT are discussed, and next steps in this field are proposed. FLASH-RT has potential but is associated with significant risks and complexities. We need to redefine optimization to focus not only on the dose but also on the dose rate in a manner that is robust and understandable and that can be prescribed, validated, and confirmed in real time. Robust patient safety systems and access to treatment data will be critical as FLASH-RT moves into the clinical trials.
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Affiliation(s)
- Wei Zou
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA.
| | - Rongxiao Zhang
- Department of Radiation Oncology, Geisel School of Medicine, Dartmouth College, Hanover, NH, USA
| | - Emil Schüler
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Paige A Taylor
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | | | - Eric S Diffenderfer
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA
| | - Tianyu Zhao
- Department of Radiation Oncology, Washington University, St. Louis, MO, USA
| | - Ahmet S Ayan
- Department of Radiation Oncology, Ohio State University, Columbus, OH, USA
| | - Manju Sharma
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, USA
| | - Shu-Jung Yu
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Weiguo Lu
- Department of Radiation Oncology, University of Texas Southwestern, Dallas, TX, USA
| | - Walter R Bosch
- Department of Radiation Oncology, Washington University, St. Louis, MO, USA
| | - Christina Tsien
- Department of Radiation Oncology, McGill University Health Center, Montreal, QC, Canada
| | - Murat Surucu
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Julianne M Pollard-Larkin
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jan Schuemann
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Eduardo G Moros
- Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL, USA
| | | | - David J Gladstone
- Department of Radiation Oncology, Geisel School of Medicine, Dartmouth College, Hanover, NH, USA
| | - Heng Li
- Department of Radiation Oncology, Johns Hopkins University, Baltimore, MD, USA
| | - Charles B Simone
- Department of Radiation Oncology, New York Proton Center, New York, NY, USA
| | - Kristoffer Petersson
- Department of Radiation Oncology, MRC Oxford Institute for Radiation Oncology, University of Oxford, Oxford, UK
| | - Stephen F Kry
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Amit Maity
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA
| | - Billy W Loo
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
| | - Lei Dong
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA
| | - Peter G Maxim
- Department of Radiation Oncology, University of California Irvine, Irvine, CA, USA
| | - Ying Xiao
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA
| | - Jeffrey C Buchsbaum
- Radiation Research Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute, National Institute of Health, Bethesda, MD, USA
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5
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Schulte R, Johnstone C, Boucher S, Esarey E, Geddes CGR, Kravchenko M, Kutsaev S, Loo BW, Méot F, Mustapha B, Nakamura K, Nanni EA, Obst-Huebl L, Sampayan SE, Schroeder CB, Sheng K, Snijders AM, Snively E, Tantawi SG, Van Tilborg J. Transformative Technology for FLASH Radiation Therapy. APPLIED SCIENCES (BASEL, SWITZERLAND) 2023; 13:5021. [PMID: 38240007 PMCID: PMC10795821 DOI: 10.3390/app13085021] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/22/2024]
Abstract
The general concept of radiation therapy used in conventional cancer treatment is to increase the therapeutic index by creating a physical dose differential between tumors and normal tissues through precision dose targeting, image guidance, and radiation beams that deliver a radiation dose with high conformality, e.g., protons and ions. However, the treatment and cure are still limited by normal tissue radiation toxicity, with the corresponding side effects. A fundamentally different paradigm for increasing the therapeutic index of radiation therapy has emerged recently, supported by preclinical research, and based on the FLASH radiation effect. FLASH radiation therapy (FLASH-RT) is an ultra-high-dose-rate delivery of a therapeutic radiation dose within a fraction of a second. Experimental studies have shown that normal tissues seem to be universally spared at these high dose rates, whereas tumors are not. While dose delivery conditions to achieve a FLASH effect are not yet fully characterized, it is currently estimated that doses delivered in less than 200 ms produce normal-tissue-sparing effects, yet effectively kill tumor cells. Despite a great opportunity, there are many technical challenges for the accelerator community to create the required dose rates with novel compact accelerators to ensure the safe delivery of FLASH radiation beams.
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Affiliation(s)
- Reinhard Schulte
- Division of Biomedical Engineering Sciences, Loma Linda University, Loma Linda, CA 92350, USA
| | - Carol Johnstone
- Fermi National Accelerator Laboratory, Batavia, IL 60510, USA
| | - Salime Boucher
- RadiaBeam Technologies, LLC, Santa Monica, CA 90404, USA
| | - Eric Esarey
- Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | | | | | - Sergey Kutsaev
- RadiaBeam Technologies, LLC, Santa Monica, CA 90404, USA
| | - Billy W. Loo
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - François Méot
- Brookhaven National Laboratory, Upton, NY 11973, USA
| | | | - Kei Nakamura
- Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Emilio A. Nanni
- SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | | | - Stephen E. Sampayan
- Lawrence Livermore National Laboratory, Livermore, CA 94551, USA
- Opcondys, Inc., Manteca, CA 95336, USA
| | | | - Ke Sheng
- Department of Radiation Oncology, University of California, San Francisco, CA 94115, USA
| | | | - Emma Snively
- SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Sami G. Tantawi
- SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
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Espinosa-Rodriguez A, Villa-Abaunza A, Díaz N, Pérez-Díaz M, Sánchez-Parcerisa D, Udías J, Ibáñez P. Design of an X-ray irradiator based on a standard imaging X-ray tube with FLASH dose-rate capabilities for preclinical research. Radiat Phys Chem Oxf Engl 1993 2023. [DOI: 10.1016/j.radphyschem.2023.110760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Hart A, Cecchi D, Giguère C, Larose F, Therriault-Proulx F, Esplen N, Beaulieu L, Bazalova-Carter M. Lead-doped scintillator dosimeters for detection of ultrahigh dose-rate x-rays. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac69a5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 04/22/2022] [Indexed: 11/12/2022]
Abstract
Abstract
Objective. Lead-doped scintillator dosimeters may be well suited for the dosimetry of FLASH-capable x-ray radiotherapy beams. Our study explores the dose rate dependence and temporal resolution of scintillators that makes them promising in the accurate detection of ultrahigh dose-rate (UHDR) x-rays. Approach. We investigated the response of scintillators with four material compositions to UHDR x-rays produced by a conventional x-ray tube. Scintillator output was measured using the HYPERSCINT-RP100 dosimetry research platform. Measurements were acquired at high frame rates (400 fps) which allowed for accurate dose measurements of sub-second radiation exposures from 1 to 100 ms. Dose-rate dependence was assessed by scaling tube current of the x-ray tube. Scintillator measurements were validated against Monte Carlo simulations of the probe geometries and UHDR x-ray system. Calibration factors converting dose-to-medium to dose-to-water were obtained from simulation data of plastic and lead-doped scintillator materials. Main Results. The results of this work suggest that lead-doped scintillators were dose-rate independent for UHDR x-rays from 1.1 to 40.1 Gy s−1 and capable of measuring conventional radiotherapy dose-rates (0.1 Gy s−1) at extended distance from the x-ray focal spot. Dose-to-water measured with a 5% lead-doped scintillator detector agreed with simulations within 0.6%. Significance. Lead-doped scintillators may be a valuable tool for the accurate real-time dosimetry of FLASH-capable UHDR x-ray beams.
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Esplen N, Egoriti L, Paley B, Planche T, Hoehr C, Gottberg A, Bazalova-Carter M. Design optimization of an electron-to-photon conversion target for ultra-high dose rate x-ray (FLASH) experiments at TRIUMF. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac5ed6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 03/17/2022] [Indexed: 12/29/2022]
Abstract
Abstract
Objective. To develop a bremsstrahlung target and megavoltage (MV) x-ray irradiation platform for ultrahigh dose-rate (UHDR) irradiation of small-animals on the Advanced Rare Isotope Laboratory (ARIEL) electron linac (e-linac) at TRIUMF. Approach. An electron-to-photon converter design for UHDR radiotherapy (RT) was centered around optimization of a tantalum–aluminum (Ta–Al) explosion-bonded target. Energy deposition within a homogeneous water-phantom and the target itself were evaluated using EGSnrc and FLUKA MC codes, respectively, for various target thicknesses (0.5–1.5 mm), beam energies (E
e− = 8, 10 MeV) and electron (Gaussian) beam sizes (
2
σ
= 2–10 mm). Depth dose-rates in a 3D-printed mouse phantom were also calculated to infer the compatibility of the 10 MV dose distributions for FLASH-RT in small-animal models. Coupled thermo-mechanical FEA simulations in ANSYS were subsequently used to inform the stress–strain conditions and fatigue life of the target assembly. Main results. Dose-rates of up to 128 Gy s−1 at the phantom surface, or 85 Gy s−1 at 1 cm depth, were obtained for a 1 × 1 cm2 field size, 1 mm thick Ta target and 7.5 cm source-to-surface distance using the FLASH-mode beam (E
e− = 10 MeV, 2
σ
= 5 mm, P = 1 kW); furthermore, removal of the collimation assembly and using a shorter (3.5 cm) SSD afforded dose-rates >600 Gy s−1, albeit at the expense of field conformality. Target temperatures were maintained below the tantalum, aluminum and cooling-water thresholds of 2000 °C, 300 °C and 100 °C, respectively, while the aluminum strain behavior remained everywhere elastic and helped ensure the converter survives its prescribed 5 yr operational lifetime. Significance. Effective design iteration, target cooling and failure mitigation have culminated in a robust target compatible with intensive transient (FLASH) and steady-state (diagnostic) applications. The ARIEL UHDR photon source will facilitate FLASH-RT experiments concerned with sub-second, pulsed or continuous beam irradiations at dose rates in excess of 40 Gy s−1.
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9
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Montay-Gruel P, Corde S, Laissue JA, Bazalova-Carter M. FLASH radiotherapy with photon beams. Med Phys 2021; 49:2055-2067. [PMID: 34519042 DOI: 10.1002/mp.15222] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 08/12/2021] [Accepted: 08/30/2021] [Indexed: 12/16/2022] Open
Abstract
Ultra-high-dose rate "FLASH" radiotherapy (FLASH-RT) has been shown to drastically reduce normal tissue toxicities while being as efficacious as conventional dose rate radiotherapy to treat tumors. A large number of preclinical studies describing this so-called FLASH effect have led to the clinical translation of FLASH-RT using ultra-high-dose rate electron and proton beams. Although the vast majority of radiation therapy treatments are delivered using X-rays, few preclinical data using ultra-high-dose rate X-ray irradiation have been published. This review focuses on different methods that can be used to generate ultra-high-dose rate X-rays and their beam characteristics along with their effect on the biological tissues and the perspectives for the development of FLASH-RT with X-rays.
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Affiliation(s)
- Pierre Montay-Gruel
- Department of Radiation Oncology, University of California, Irvine, California, USA.,Department of Radiotherapy, Iridium Network, Antwerp, Belgium
| | - Stéphanie Corde
- Department of Radiation Oncology, Prince of Wales Hospital, Randwick, NSW, Australia.,Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, Australia.,Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia
| | - Jean A Laissue
- Institute of Pathology, University of Bern, Bern, Switzerland
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