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Hachadorian R, Cascio E, Schuemann J. Increased flexibility and efficiency of a double-scattering FLASH proton beamline configuration for in vivoSOBP radiotherapy treatments. Phys Med Biol 2023; 68:10.1088/1361-6560/ace23c. [PMID: 37369231 PMCID: PMC10652226 DOI: 10.1088/1361-6560/ace23c] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 06/27/2023] [Indexed: 06/29/2023]
Abstract
Objective. To commission a proton, double-scattering FLASH beamline by maximizing efficiency and field size, enabling higher-linear energy transfer FLASH radiotherapy to cells and small animals using a spread-out Bragg peak (SOBP) treatment configuration. We further aim to provide a configuration guide for the design of future FLASH proton double-scattering (DS) beamlines.Approach. Beam spot size and spread were measured with film and implemented into TOol for PArticle Simulation (TOPAS). Monte Carlo simulations were optimized to verify the ideal positioning, dimensions, and material of scattering foils, secondary scatterers, ridge filters, range compensators, and apertures. A ridge filter with three discrete heights was used to create a spread-out Bragg peak (SOBP) and was experimentally verified using our in-house experimental FLASH beamline. The increase in dose rate was compared to nominal shoot-through techniques.Results. The configuration and scatterer distance producing the largest field size of acceptable flatness, without drastically compromising dose rate was determined to be an elliptical field of 2 cm × 1.5 cm (25% larger than a previous configuration). SOBP testing yielded three distinct but connected spikes in dose with flatness under 5%. Reducing the thickness of the (first) scattering foil by a factor of two was found to increase efficiency by 50%. The new settings increased the field size, provided a Bragg peak treatment option, and increased the maximum available dose rate by 85%, as compared to the previous, shoot through method.Significance. Beam line updates established FLASH dose rates of over 135 Gy s-1(potentially higher) at our double-scattering beamline, increased the efficiency and field size, and enabled SOBP treatments by incorporating an optimized ridge filter. Based on our simulations we provide parametric suggestions when commissioning a new proton DS beamline. This enhanced FLASH beamline for SOBP irradiations with higher dose rates and larger field sizes will enable a wider variety of experimentation in future studies.
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Affiliation(s)
- R. Hachadorian
- Massachusetts General Hospital Division of Radiation Oncology, 55 Fruit Street, Boston, MA 02114
- Harvard Medical School - Massachusetts General Hospital, 55 Fruit Street, Boston, MA 02114
| | - E. Cascio
- Massachusetts General Hospital Division of Radiation Oncology, 55 Fruit Street, Boston, MA 02114
| | - J. Schuemann
- Massachusetts General Hospital Division of Radiation Oncology, 55 Fruit Street, Boston, MA 02114
- Harvard Medical School - Massachusetts General Hospital, 55 Fruit Street, Boston, MA 02114
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Schuemann J. FLASH Mechanisms Track MODELLING THE MECHANISMS OF THE FLASH EFFECT. Phys Med 2022. [DOI: 10.1016/s1120-1797(22)01447-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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D-Kondo N, Moreno-Barbosa E, Štěphán V, Stefanová K, Perrot Y, Villagrasa C, Incerti S, De Celis Alonso B, Schuemann J, Faddegon B, Ramos-Méndez J. DNA damage modeled with Geant4-DNA: effects of plasmid DNA conformation and experimental conditions. Phys Med Biol 2021; 66. [PMID: 34787099 DOI: 10.1088/1361-6560/ac3a22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 09/03/2021] [Accepted: 11/16/2021] [Indexed: 12/13/2022]
Abstract
The chemical stage of the Monte Carlo track-structure (MCTS) code Geant4-DNA was extended for its use in DNA strand break (SB) simulations and compared against published experimental data. Geant4-DNA simulations were performed using pUC19 plasmids (2686 base pairs) in a buffered solution of DMSO irradiated by60Co or137Csγ-rays. A comprehensive evaluation of SSB yields was performed considering DMSO, DNA concentration, dose and plasmid supercoiling. The latter was measured using the super helix density value used in a Brownian dynamics plasmid generation algorithm. The Geant4-DNA implementation of the independent reaction times method (IRT), developed to simulate the reaction kinetics of radiochemical species, allowed to score the fraction of supercoiled, relaxed and linearized plasmid fractions as a function of the absorbed dose. The percentage of the number of SB after •OH + DNA and H• + DNA reactions, referred as SSB efficiency, obtained using MCTS were 13.77% and 0.74% respectively. This is in reasonable agreement with published values of 12% and 0.8%. The SSB yields as a function of DMSO concentration, DNA concentration and super helix density recreated the expected published experimental behaviors within 5%, one standard deviation. The dose response of SSB and DSB yields agreed with published measurements within 5%, one standard deviation. We demonstrated that the developed extension of IRT in Geant4-DNA, facilitated the reproduction of experimental conditions. Furthermore, its calculations were strongly in agreement with experimental data. These two facts will facilitate the use of this extension in future radiobiological applications, aiding the study of DNA damage mechanisms with a high level of detail.
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Affiliation(s)
- N D-Kondo
- Faculty of Mathematics and Physics Sciences, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - E Moreno-Barbosa
- Faculty of Mathematics and Physics Sciences, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - V Štěphán
- Department of Radiation Dosimetry, Nuclear Physics Institute of the Czech Academy of Sciences, Prague, Czech Republic
| | - K Stefanová
- Department of Radiation Dosimetry, Nuclear Physics Institute of the Czech Academy of Sciences, Prague, Czech Republic
| | - Y Perrot
- Laboratoire de Dosimétrie des Rayonnements Ionisants, Institut de Radioprotection et Sûreté Nucléaire, Fontenay aux Roses, BP. 17, F-92262, France
| | - C Villagrasa
- Laboratoire de Dosimétrie des Rayonnements Ionisants, Institut de Radioprotection et Sûreté Nucléaire, Fontenay aux Roses, BP. 17, F-92262, France
| | - S Incerti
- Univ. Bordeaux, CNRS/IN2P3, CENBG, UMR 5797, F-33170 Gradignan, France
| | - B De Celis Alonso
- Faculty of Mathematics and Physics Sciences, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - J Schuemann
- Department of Radiation Oncology, Massachusets General Hospital and Hardvard Medical School, Boston, MA, United States of America
| | - B Faddegon
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, United States of America
| | - J Ramos-Méndez
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, United States of America
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Ramos-Méndez J, LaVerne JA, Domínguez-Kondo N, Milligan J, Štěpán V, Stefanová K, Perrot Y, Villagrasa C, Shin WG, Incerti S, McNamara A, Paganetti H, Perl J, Schuemann J, Faddegon B. TOPAS-nBio validation for simulating water radiolysis and DNA damage under low-LET irradiation. Phys Med Biol 2021; 66. [PMID: 34412044 DOI: 10.1088/1361-6560/ac1f39] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [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: 06/01/2021] [Accepted: 08/19/2021] [Indexed: 11/12/2022]
Abstract
The chemical stage of the Monte Carlo track-structure simulation code Geant4-DNA has been revised and validated. The root-mean-square (RMS) empirical parameter that dictates the displacement of water molecules after an ionization and excitation event in Geant4-DNA has been shortened to better fit experimental data. The pre-defined dissociation channels and branching ratios were not modified, but the reaction rate coefficients for simulating the chemical stage of water radiolysis were updated. The evaluation of Geant4-DNA was accomplished with TOPAS-nBio. For that, we compared predicted time-dependentGvalues in pure liquid water for·OH, e-aq, and H2with published experimental data. For H2O2and H·, simulation of added scavengers at different concentrations resulted in better agreement with measurements. In addition, DNA geometry information was integrated with chemistry simulation in TOPAS-nBio to realize reactions between radiolytic chemical species and DNA. This was used in the estimation of the yield of single-strand breaks (SSB) induced by137Csγ-ray radiolysis of supercoiled pUC18 plasmids dissolved in aerated solutions containing DMSO. The efficiency of SSB induction by reaction between radiolytic species and DNA used in the simulation was chosen to provide the best agreement with published measurements. An RMS displacement of 1.24 nm provided agreement with measured data within experimental uncertainties for time-dependentGvalues and under the presence of scavengers. SSB efficiencies of 24% and 0.5% for·OH and H·, respectively, led to an overall agreement of TOPAS-nBio results within experimental uncertainties. The efficiencies obtained agreed with values obtained with published non-homogeneous kinetic model and step-by-step Monte Carlo simulations but disagreed by 12% with published direct measurements. Improvement of the spatial resolution of the DNA damage model might mitigate such disagreement. In conclusion, with these improvements, Geant4-DNA/TOPAS-nBio provides a fast, accurate, and user-friendly tool for simulating DNA damage under low linear energy transfer irradiation.
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Affiliation(s)
- J Ramos-Méndez
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA 94115, United States of America
| | - J A LaVerne
- Radiation Laboratory and Department of Physics, University of Notre Dame, Notre Dame, IN 46556, United States of America
| | - N Domínguez-Kondo
- Facultad de Ciencias Físico Matemáticas, Benemérita Universidad Autónoma de Puebla, Puebla 72000, Mexico
| | - J Milligan
- Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, 92350, United States of America
| | - V Štěpán
- Department of Radiation Dosimetry, Nuclear Physics Institute of the Czech Academy of Sciences, Prague, Czech Republic
| | - K Stefanová
- Department of Radiation Dosimetry, Nuclear Physics Institute of the Czech Academy of Sciences, Prague, Czech Republic
| | - Y Perrot
- Laboratoire de Dosimétrie des Rayonnements Ionisants, Institut de Radioprotection et Sûreté Nucléaire, Fontenay aux Roses, BP. 17, F-92262, France
| | - C Villagrasa
- Laboratoire de Dosimétrie des Rayonnements Ionisants, Institut de Radioprotection et Sûreté Nucléaire, Fontenay aux Roses, BP. 17, F-92262, France
| | - W-G Shin
- Department of Radiation Oncology, Seoul National University Hospital, Seoul 03080, Republic of Korea
| | - S Incerti
- Univ. Bordeaux, CNRS, CENBG, UMR 5797, F-33170 Gradignan, France
| | - A McNamara
- Department of Radiation Oncology, Physics Division, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - H Paganetti
- Department of Radiation Oncology, Physics Division, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - J Perl
- SLAC National Accelerator Laboratory, Menlo Park, CA, United States of America
| | - J Schuemann
- Department of Radiation Oncology, Physics Division, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America
| | - B Faddegon
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA 94115, United States of America
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Schuemann J. Challenging early target safety assessment strategies. Toxicol Lett 2021. [DOI: 10.1016/s0378-4274(21)00256-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Rabus H, Li WB, Nettelbeck H, Schuemann J, Villagrasa C, Beuve M, Di Maria S, Heide B, Klapproth AP, Poignant F, Qiu R, Rudek B. Consistency checks of results from a Monte Carlo code intercomparison for emitted electron spectra and energy deposition around a single gold nanoparticle irradiated by X-rays. RADIAT MEAS 2021; 147:106637. [PMID: 35669292 PMCID: PMC9165644 DOI: 10.1016/j.radmeas.2021.106637] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Organized by the European Radiation Dosimetry Group (EURADOS), a Monte Carlo code intercomparison exercise was conducted where participants simulated the emitted electron spectra and energy deposition around a single gold nanoparticle (GNP) irradiated by X-rays. In the exercise, the participants scored energy imparted in concentric spherical shells around a spherical volume filled with gold or water as well as the spectral distribution of electrons leaving the GNP. Initially, only the ratio of energy deposition with and without GNP was to be reported. During the evaluation of the exercise, however, the data for energy deposition in the presence and absence of the GNP were also requested. A GNP size of 50 nm and 100 nm diameter was considered as well as two different X-ray spectra (50 kVp and 100kVp). This introduced a redundancy that can be used to cross-validate the internal consistency of the simulation results. In this work, evaluation of the reported results is presented in terms of integral quantities that can be benchmarked against values obtained from physical properties of the radiation spectra and materials involved. The impact of different interaction cross-section datasets and their implementation in the different Monte Carlo codes is also discussed.
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Affiliation(s)
- H Rabus
- Physikalisch-Technische Bundesanstalt, Braunschweig and Berlin, Germany
- European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - W B Li
- Institute of Radiation Medicine, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
- European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - H Nettelbeck
- Physikalisch-Technische Bundesanstalt, Braunschweig and Berlin, Germany
- European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - J Schuemann
- Massachusetts General Hospital & Harvard Medical School, Department of Radiation Oncology, Boston, MA, USA
- European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - C Villagrasa
- Institut de Radioprotection et de Sûreté Nucléaire, Fontenay-Aux-Roses, France
- European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - M Beuve
- Institut de Physique des 2 Infinis, Université Claude Bernard Lyon 1, Villeurbanne, France
- European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - S Di Maria
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Bobadela LRS, Portugal
- European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - B Heide
- Karlsruhe Institute of Technology, Karlsruhe, Germany
- European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - A P Klapproth
- Institute of Radiation Medicine, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
- TranslaTUM, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - F Poignant
- Institut de Physique des 2 Infinis, Université Claude Bernard Lyon 1, Villeurbanne, France
- Present address: National Institute of Aerospace, Hampton, VA, USA
| | - R Qiu
- Department of Engineering Physics, Tsinghua University, Beijing, China
- European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - B Rudek
- Massachusetts General Hospital & Harvard Medical School, Department of Radiation Oncology, Boston, MA, USA
- Present address: Perlmutter Cancer Center, NYU Langone Health, New York City, NY, USA
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Rabus H, Li WB, Villagrasa C, Schuemann J, Hepperle PA, de la Fuente Rosales L, Beuve M, Di Maria S, Klapproth AP, Li CY, Poignant F, Rudek B, Nettelbeck H. Intercomparison of Monte Carlo calculated dose enhancement ratios for gold nanoparticles irradiated by X-rays: Assessing the uncertainty and correct methodology for extended beams. Phys Med 2021; 84:241-253. [PMID: 33766478 DOI: 10.1016/j.ejmp.2021.03.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 02/24/2021] [Accepted: 03/01/2021] [Indexed: 12/12/2022] Open
Abstract
Results of a Monte Carlo code intercomparison exercise for simulations of the dose enhancement from a gold nanoparticle (GNP) irradiated by X-rays have been recently reported. To highlight potential differences between codes, the dose enhancement ratios (DERs) were shown for the narrow-beam geometry used in the simulations, which leads to values significantly higher than unity over distances in the order of several tens of micrometers from the GNP surface. As it has come to our attention that the figures in our paper have given rise to misinterpretation as showing 'the' DERs of GNPs under diagnostic X-ray irradiation, this article presents estimates of the DERs that would have been obtained with realistic radiation field extensions and presence of secondary particle equilibrium (SPE). These DER values are much smaller than those for a narrow-beam irradiation shown in our paper, and significant dose enhancement is only found within a few hundred nanometers around the GNP. The approach used to obtain these estimates required the development of a methodology to identify and, where possible, correct results from simulations whose implementation deviated from the initial exercise definition. Based on this methodology, literature on Monte Carlo simulated DERs has been critically assessed.
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Affiliation(s)
- H Rabus
- Physikalisch-Technische Bundesanstalt, Braunschweig and Berlin, Germany; European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - W B Li
- Institute of Radiation Medicine, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany; European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - C Villagrasa
- Institut de Radioprotection et de Sûreté Nucléaire, Fontenay-Aux-Roses, France; European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - J Schuemann
- Massachusetts General Hospital & Harvard Medical School, Department of Radiation Oncology, Boston, MA, USA; European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - P A Hepperle
- Physikalisch-Technische Bundesanstalt, Braunschweig and Berlin, Germany; Leibniz Universität Hannover, Hannover, Germany
| | | | - M Beuve
- Institut de Physique des 2 Infinis, Université Claude Bernard Lyon 1, Villeurbanne, France; European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - S Di Maria
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Bobadela LRS, Portugal; European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
| | - A P Klapproth
- Institute of Radiation Medicine, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany; TranslaTUM, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - C Y Li
- Department of Engineering Physics, Tsinghua University, Beijing, China; Nuctech Company Limited, Beijing, China
| | - F Poignant
- Institut de Physique des 2 Infinis, Université Claude Bernard Lyon 1, Villeurbanne, France; NASA Langley Research Center, Hampton, VA, USA
| | - B Rudek
- Physikalisch-Technische Bundesanstalt, Braunschweig and Berlin, Germany; Massachusetts General Hospital & Harvard Medical School, Department of Radiation Oncology, Boston, MA, USA; Perlmutter Cancer Center, NYU Langone Health, New York City, NY, USA
| | - H Nettelbeck
- Physikalisch-Technische Bundesanstalt, Braunschweig and Berlin, Germany; European Radiation Dosimetry Group (EURADOS) e.V, Neuherberg, Germany
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Ramos-Méndez J, Domínguez-Kondo N, Schuemann J, McNamara A, Moreno-Barbosa E, Faddegon B. LET-Dependent Intertrack Yields in Proton Irradiation at Ultra-High Dose Rates Relevant for FLASH Therapy. Radiat Res 2020; 194:351-362. [PMID: 32857855 PMCID: PMC7644138 DOI: 10.1667/rade-20-00084.1] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [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: 03/23/2020] [Accepted: 07/13/2020] [Indexed: 01/01/2023]
Abstract
FLASH radiotherapy delivers a high dose (≥10 Gy) at a high rate (≥40 Gy/s). In this way, particles are delivered in pulses as short as a few nanoseconds. At that rate, intertrack reactions between chemical species produced within the same pulse may affect the heterogeneous chemistry stage of water radiolysis. This stochastic process suits the capabilities of the Monte Carlo method, which can model intertrack effects to aid in radiobiology research, including the design and interpretation of experiments. In this work, the TOPAS-nBio Monte Carlo track-structure code was expanded to allow simulations of intertrack effects in the chemical stage of water radiolysis. Simulation of the behavior of radiolytic yields over a long period of time (up to 50 s) was verified by simulating radiolysis in a Fricke dosimeter irradiated by 60Co γ rays. In addition, LET-dependent G values of protons delivered in single squared pulses of widths, 1 ns, 1 µs and 10 µs, were obtained and compared to simulations using no intertrack considerations. The Fricke simulation for the calculated G value of Fe3+ ion at 50 s was within 0.4% of the accepted value from ICRU Report 34. For LET-dependent G values at the end of the chemical stage, intertrack effects were significant at LET values below 2 keV/µm. Above 2 keV/µm the reaction kinetics remained limited locally within each track and thus, effects of intertrack reactions remained low. Therefore, when track structure simulations are used to investigate the biological damage of FLASH irradiation, these intertrack reactions should be considered. The TOPAS-nBio framework with the expansion to intertrack chemistry simulation provides a useful tool to assist in this task.
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Affiliation(s)
- J. Ramos-Méndez
- Department of Radiation Oncology, University of California San Francisco, San Francisco, California
| | - N. Domínguez-Kondo
- Facultad de Ciencias Físico-Matemáticas, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - J. Schuemann
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - A. McNamara
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - E. Moreno-Barbosa
- Facultad de Ciencias Físico-Matemáticas, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - Bruce Faddegon
- Department of Radiation Oncology, University of California San Francisco, San Francisco, California
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Li WB, Belchior A, Beuve M, Chen YZ, Di Maria S, Friedland W, Gervais B, Heide B, Hocine N, Ipatov A, Klapproth AP, Li CY, Li JL, Multhoff G, Poignant F, Qiu R, Rabus H, Rudek B, Schuemann J, Stangl S, Testa E, Villagrasa C, Xie WZ, Zhang YB. Intercomparison of dose enhancement ratio and secondary electron spectra for gold nanoparticles irradiated by X-rays calculated using multiple Monte Carlo simulation codes. Phys Med 2020; 69:147-163. [PMID: 31918367 DOI: 10.1016/j.ejmp.2019.12.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 11/29/2019] [Accepted: 12/15/2019] [Indexed: 12/22/2022] Open
Abstract
PURPOSE Targeted radiation therapy has seen an increased interest in the past decade. In vitro and in vivo experiments showed enhanced radiation doses due to gold nanoparticles (GNPs) to tumors in mice and demonstrated a high potential for clinical application. However, finding a functionalized molecular formulation for actively targeting GNPs in tumor cells is challenging. Furthermore, the enhanced energy deposition by secondary electrons around GNPs, particularly by short-ranged Auger electrons is difficult to measure. Computational models, such as Monte Carlo (MC) radiation transport codes, have been used to estimate the physical quantities and effects of GNPs. However, as these codes differ from one to another, the reliability of physical and dosimetric quantities needs to be established at cellular and molecular levels, so that the subsequent biological effects can be assessed quantitatively. METHODS In this work, irradiation of single GNPs of 50 nm and 100 nm diameter by X-ray spectra generated by 50 and 100 peak kilovoltages was simulated for a defined geometry setup, by applying multiple MC codes in the EURADOS framework. RESULTS The mean dose enhancement ratio of the first 10 nm-thick water shell around a 100 nm GNP ranges from 400 for 100 kVp X-rays to 600 for 50 kVp X-rays with large uncertainty factors up to 2.3. CONCLUSIONS It is concluded that the absolute dose enhancement effects have large uncertainties and need an inter-code intercomparison for a high quality assurance; relative properties may be a better measure until more experimental data is available to constrain the models.
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Affiliation(s)
- W B Li
- Institute of Radiation Medicine, Helmholtz Zentrum München - German Research Center for Environmental Health (GmbH), Ingolstädter Landstr. 1, 85764 Neuherberg, Germany.
| | - A Belchior
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, 2695-066 Bobadela LRS, Portugal
| | - M Beuve
- Institut de Physique Nucléaire de Lyon, Université de Lyon, Université Claude Bernard Lyon 1, CNRS/IN2P3 UMR 5822, Villeurbanne, France
| | - Y Z Chen
- Department of Engineering Physics, Tsinghua University, Beijing, China
| | - S Di Maria
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, 2695-066 Bobadela LRS, Portugal
| | - W Friedland
- Institute of Radiation Medicine, Helmholtz Zentrum München - German Research Center for Environmental Health (GmbH), Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - B Gervais
- Normandie University, ENSICAEN, UNICAEN, CEA, CNRS, CIMAP, UMR 6252, BP 5133, F-14070 Caen Cedex 05, France
| | - B Heide
- Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - N Hocine
- Institut de Radioprotection et de Sûreté Nucléaire, Fontenay-Aux-Roses, France
| | - A Ipatov
- Alferov Federal State Budgetary Institution of Higher Education and Science Saint Petersburg National Research Academic University of the Russian Academy of Sciences, St. Petersburg, Russia
| | - A P Klapproth
- Institute of Radiation Medicine, Helmholtz Zentrum München - German Research Center for Environmental Health (GmbH), Ingolstädter Landstr. 1, 85764 Neuherberg, Germany; TranslaTUM, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - C Y Li
- Department of Engineering Physics, Tsinghua University, Beijing, China; Nuctech Company Limited, Beijing, China
| | - J L Li
- Department of Engineering Physics, Tsinghua University, Beijing, China
| | - G Multhoff
- TranslaTUM, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - F Poignant
- Institut de Physique Nucléaire de Lyon, Université de Lyon, Université Claude Bernard Lyon 1, CNRS/IN2P3 UMR 5822, Villeurbanne, France
| | - R Qiu
- Department of Engineering Physics, Tsinghua University, Beijing, China
| | - H Rabus
- Physikalisch-Technische Bundesanstalt, Braunschweig, Germany
| | - B Rudek
- Physikalisch-Technische Bundesanstalt, Braunschweig, Germany; Massachusetts General Hospital & Harvard Medical School, Department of Radiation Oncology, Boston, MA, USA
| | - J Schuemann
- Massachusetts General Hospital & Harvard Medical School, Department of Radiation Oncology, Boston, MA, USA
| | - S Stangl
- TranslaTUM, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - E Testa
- Institut de Physique Nucléaire de Lyon, Université de Lyon, Université Claude Bernard Lyon 1, CNRS/IN2P3 UMR 5822, Villeurbanne, France
| | - C Villagrasa
- Institut de Radioprotection et de Sûreté Nucléaire, Fontenay-Aux-Roses, France
| | - W Z Xie
- Department of Engineering Physics, Tsinghua University, Beijing, China
| | - Y B Zhang
- Peking University Cancer Hospital, Beijing, China
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Schuemann J, McNamara AL, Ramos-Méndez J, Perl J, Held KD, Paganetti H, Incerti S, Faddegon B. TOPAS-nBio: An Extension to the TOPAS Simulation Toolkit for Cellular and Sub-cellular Radiobiology. Radiat Res 2019; 191:125-138. [PMID: 30609382 DOI: 10.1667/rr15226.1] [Citation(s) in RCA: 104] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The TOPAS Monte Carlo (MC) system is used in radiation therapy and medical imaging research, having played a significant role in making Monte Carlo simulations widely available for proton therapy related research. While TOPAS provides detailed simulations of patient scale properties, the fundamental unit of the biological response to radiation is a cell. Thus, our goal was to develop TOPAS-nBio, an extension of TOPAS dedicated to advance understanding of radiobiological effects at the (sub-)cellular, (i.e., the cellular and sub-cellular) scale. TOPAS-nBio was designed as a set of open source classes that extends TOPAS to model radiobiological experiments. TOPAS-nBio is based on and extends Geant4-DNA, which extends the Geant4 toolkit, the basis of TOPAS, to include very low-energy interactions of particles down to vibrational energies, explicitly simulates every particle interaction (i.e., without using condensed histories) and propagates radiolysis products. To further facilitate the use of TOPAS-nBio, a graphical user interface was developed. TOPAS-nBio offers full track-structure Monte Carlo simulations, integration of chemical reactions within the first millisecond, an extensive catalogue of specialized cell geometries as well as sub-cellular structures such as DNA and mitochondria, and interfaces to mechanistic models of DNA repair kinetics. We compared TOPAS-nBio simulations to measured and published data of energy deposition patterns and chemical reaction rates (G values). Our simulations agreed well within the experimental uncertainties. Additionally, we expanded the chemical reactions and species provided in Geant4-DNA and developed a new method based on independent reaction times (IRT), including a total of 72 reactions classified into 6 types between neutral and charged species. Chemical stage simulations using IRT were a factor of 145 faster than with step-by-step tracking. Finally, we applied the geometric/chemical modeling to obtain initial yields of double-strand breaks (DSBs) in DNA fibers for proton irradiations of 3 and 50 MeV and compared the effect of including chemical reactions on the number and complexity of DSB induction. Over half of the DSBs were found to include chemical reactions with approximately 5% of DSBs caused only by chemical reactions. In conclusion, the TOPAS-nBio extension to the TOPAS MC application offers access to accurate and detailed multiscale simulations, from a macroscopic description of the radiation field to microscopic description of biological outcome for selected cells. TOPAS-nBio offers detailed physics and chemistry simulations of radiobiological experiments on cells simulating the initially induced damage and links to models of DNA repair kinetics.
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Affiliation(s)
- J Schuemann
- a Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - A L McNamara
- a Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - J Ramos-Méndez
- b Department of Radiation Oncology, University of California San Francisco, San Francisco, California
| | - J Perl
- c SLAC National Accelerator Laboratory, Menlo Park, California
| | - K D Held
- a Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - H Paganetti
- a Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - S Incerti
- d CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan, France.,e University of Bordeaux, CENBG, UMR 5797, F-33170 Gradignan, France
| | - B Faddegon
- b Department of Radiation Oncology, University of California San Francisco, San Francisco, California
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11
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Schuemann J, McNamara AL, Warmenhoven JW, Henthorn NT, Kirkby KJ, Merchant MJ, Ingram S, Paganetti H, Held KD, Ramos-Mendez J, Faddegon B, Perl J, Goodhead DT, Plante I, Rabus H, Nettelbeck H, Friedland W, Kundrát P, Ottolenghi A, Baiocco G, Barbieri S, Dingfelder M, Incerti S, Villagrasa C, Bueno M, Bernal MA, Guatelli S, Sakata D, Brown JMC, Francis Z, Kyriakou I, Lampe N, Ballarini F, Carante MP, Davídková M, Štěpán V, Jia X, Cucinotta FA, Schulte R, Stewart RD, Carlson DJ, Galer S, Kuncic Z, Lacombe S, Milligan J, Cho SH, Sawakuchi G, Inaniwa T, Sato T, Li W, Solov'yov AV, Surdutovich E, Durante M, Prise KM, McMahon SJ. A New Standard DNA Damage (SDD) Data Format. Radiat Res 2018; 191:76-92. [PMID: 30407901 DOI: 10.1667/rr15209.1] [Citation(s) in RCA: 42] [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] [Indexed: 11/03/2022]
Abstract
Our understanding of radiation-induced cellular damage has greatly improved over the past few decades. Despite this progress, there are still many obstacles to fully understand how radiation interacts with biologically relevant cellular components, such as DNA, to cause observable end points such as cell killing. Damage in DNA is identified as a major route of cell killing. One hurdle when modeling biological effects is the difficulty in directly comparing results generated by members of different research groups. Multiple Monte Carlo codes have been developed to simulate damage induction at the DNA scale, while at the same time various groups have developed models that describe DNA repair processes with varying levels of detail. These repair models are intrinsically linked to the damage model employed in their development, making it difficult to disentangle systematic effects in either part of the modeling chain. These modeling chains typically consist of track-structure Monte Carlo simulations of the physical interactions creating direct damages to DNA, followed by simulations of the production and initial reactions of chemical species causing so-called "indirect" damages. After the induction of DNA damage, DNA repair models combine the simulated damage patterns with biological models to determine the biological consequences of the damage. To date, the effect of the environment, such as molecular oxygen (normoxic vs. hypoxic), has been poorly considered. We propose a new standard DNA damage (SDD) data format to unify the interface between the simulation of damage induction in DNA and the biological modeling of DNA repair processes, and introduce the effect of the environment (molecular oxygen or other compounds) as a flexible parameter. Such a standard greatly facilitates inter-model comparisons, providing an ideal environment to tease out model assumptions and identify persistent, underlying mechanisms. Through inter-model comparisons, this unified standard has the potential to greatly advance our understanding of the underlying mechanisms of radiation-induced DNA damage and the resulting observable biological effects when radiation parameters and/or environmental conditions change.
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Affiliation(s)
- J Schuemann
- a Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - A L McNamara
- a Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - J W Warmenhoven
- b Division of Cancer Sciences, The University of Manchester, Manchester, United Kingdom
| | - N T Henthorn
- b Division of Cancer Sciences, The University of Manchester, Manchester, United Kingdom
| | - K J Kirkby
- b Division of Cancer Sciences, The University of Manchester, Manchester, United Kingdom
| | - M J Merchant
- b Division of Cancer Sciences, The University of Manchester, Manchester, United Kingdom
| | - S Ingram
- b Division of Cancer Sciences, The University of Manchester, Manchester, United Kingdom
| | - H Paganetti
- a Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - K D Held
- a Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - J Ramos-Mendez
- c Department of Radiation Oncology, University of California San Francisco, San Francisco, California
| | - B Faddegon
- c Department of Radiation Oncology, University of California San Francisco, San Francisco, California
| | - J Perl
- d SLAC National Accelerator Laboratory, Menlo Park, California
| | - D T Goodhead
- e Medical Research Council, Harwell, United Kingdom
| | | | - H Rabus
- g Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany.,h Task Group 6.2 "Computational Micro- and Nanodosimetry", European Radiation Dosimetry Group e.V., Neuherberg, Germany
| | - H Nettelbeck
- g Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany.,h Task Group 6.2 "Computational Micro- and Nanodosimetry", European Radiation Dosimetry Group e.V., Neuherberg, Germany
| | - W Friedland
- h Task Group 6.2 "Computational Micro- and Nanodosimetry", European Radiation Dosimetry Group e.V., Neuherberg, Germany.,i Institute of Radiation Protection, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - P Kundrát
- i Institute of Radiation Protection, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - A Ottolenghi
- j Physics Department, University of Pavia, Pavia, Italy
| | - G Baiocco
- h Task Group 6.2 "Computational Micro- and Nanodosimetry", European Radiation Dosimetry Group e.V., Neuherberg, Germany.,j Physics Department, University of Pavia, Pavia, Italy
| | - S Barbieri
- h Task Group 6.2 "Computational Micro- and Nanodosimetry", European Radiation Dosimetry Group e.V., Neuherberg, Germany.,j Physics Department, University of Pavia, Pavia, Italy
| | - M Dingfelder
- k Department of Physics, East Carolina University, Greenville, North Carolina
| | - S Incerti
- l CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan, France.,m University of Bordeaux, CENBG, UMR 5797, F-33170 Gradignan, France
| | - C Villagrasa
- h Task Group 6.2 "Computational Micro- and Nanodosimetry", European Radiation Dosimetry Group e.V., Neuherberg, Germany.,n Institut de Radioprotection et Sûreté Nucléaire, F-92262 Fontenay aux Roses Cedex, France
| | - M Bueno
- n Institut de Radioprotection et Sûreté Nucléaire, F-92262 Fontenay aux Roses Cedex, France
| | - M A Bernal
- o Applied Physics Department, Gleb Wataghin Institute of Physics, State University of Campinas, Campinas, SP, Brazil
| | - S Guatelli
- p Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, Australia
| | - D Sakata
- p Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, Australia
| | - J M C Brown
- q Department of Radiation Science and Technology, Delft University of Technology, Delft, The Netherlands
| | - Z Francis
- r Department of Physics, Faculty of Science, Saint Joseph University, Beirut, Lebanon
| | - I Kyriakou
- s Medical Physics Laboratory, University of Ioannina Medical School, Ioannina, Greece
| | - N Lampe
- l CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan, France
| | - F Ballarini
- j Physics Department, University of Pavia, Pavia, Italy.,t Italian National Institute of Nuclear Physics, Section of Pavia, I-27100 Pavia, Italy
| | - M P Carante
- j Physics Department, University of Pavia, Pavia, Italy.,t Italian National Institute of Nuclear Physics, Section of Pavia, I-27100 Pavia, Italy
| | - M Davídková
- u Department of Radiation Dosimetry, Nuclear Physics Institute of the CAS, Řež, Czech Republic
| | - V Štěpán
- u Department of Radiation Dosimetry, Nuclear Physics Institute of the CAS, Řež, Czech Republic
| | - X Jia
- v Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - F A Cucinotta
- w Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, Nevada
| | - R Schulte
- x Division of Biomedical Engineering Sciences, School of Medicine, Loma Linda University, Loma Linda, California
| | - R D Stewart
- y Department of Radiation Oncology, University of Washington, Seattle, Washington
| | - D J Carlson
- z Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut
| | - S Galer
- aa Medical Radiation Science Group, National Physical Laboratory, Teddington, United Kingdom
| | - Z Kuncic
- bb School of Physics, University of Sydney, Sydney, NSW, Australia
| | - S Lacombe
- cc Institut des Sciences Moléculaires d'Orsay (UMR 8214) University Paris-Sud, CNRS, University Paris-Saclay, 91405 Orsay Cedex, France
| | | | - S H Cho
- ee Department of Radiation Physics and Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - G Sawakuchi
- ee Department of Radiation Physics and Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - T Inaniwa
- ff Department of Accelerator and Medical Physics, National Institute of Radiological Sciences, Chiba, Japan
| | - T Sato
- gg Japan Atomic Energy Agency, Nuclear Science and Engineering Center, Tokai 319-1196, Japan
| | - W Li
- i Institute of Radiation Protection, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany.,hh Task Group 7.7 "Internal Micro- and Nanodosimetry", European Radiation Dosimetry Group e.V., Neuherberg, Germany
| | - A V Solov'yov
- ii MBN Research Center, 60438 Frankfurt am Main, Germany
| | - E Surdutovich
- jj Department of Physics, Oakland University, Rochester, Michigan
| | - M Durante
- kk GSI Helmholtzzentrum für Schwerionenforschung, Biophysics Department, Darmstadt, Germany
| | - K M Prise
- ll Centre for Cancer Research and Cell Biology, Queens University Belfast, Belfast, United Kingdom
| | - S J McMahon
- ll Centre for Cancer Research and Cell Biology, Queens University Belfast, Belfast, United Kingdom
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Abstract
Simulation of water radiolysis and the subsequent chemistry provides important information on the effect of ionizing radiation on biological material. The Geant4 Monte Carlo toolkit has added chemical processes via the Geant4-DNA project. The TOPAS tool simplifies the modeling of complex radiotherapy applications with Geant4 without requiring advanced computational skills, extending the pool of users. Thus, a new extension to TOPAS, TOPAS-nBio, is under development to facilitate the configuration of track-structure simulations as well as water radiolysis simulations with Geant4-DNA for radiobiological studies. In this work, radiolysis simulations were implemented in TOPAS-nBio. Users may now easily add chemical species and their reactions, and set parameters including branching ratios, dissociation schemes, diffusion coefficients, and reaction rates. In addition, parameters for the chemical stage were re-evaluated and updated from those used by default in Geant4-DNA to improve the accuracy of chemical yields. Simulation results of time-dependent and LET-dependent primary yields Gx (chemical species per 100 eV deposited) produced at neutral pH and 25 °C by short track-segments of charged particles were compared to published measurements. The LET range was 0.05-230 keV µm-1. The calculated Gx values for electrons satisfied the material balance equation within 0.3%, similar for protons albeit with long calculation time. A smaller geometry was used to speed up proton and alpha simulations, with an acceptable difference in the balance equation of 1.3%. Available experimental data of time-dependent G-values for [Formula: see text] agreed with simulated results within 7% ± 8% over the entire time range; for [Formula: see text] over the full time range within 3% ± 4%; for H2O2 from 49% ± 7% at earliest stages and 3% ± 12% at saturation. For the LET-dependent Gx, the mean ratios to the experimental data were 1.11 ± 0.98, 1.21 ± 1.11, 1.05 ± 0.52, 1.23 ± 0.59 and 1.49 ± 0.63 (1 standard deviation) for [Formula: see text], [Formula: see text], H2, H2O2 and [Formula: see text], respectively. In conclusion, radiolysis and subsequent chemistry with Geant4-DNA has been successfully incorporated in TOPAS-nBio. Results are in reasonable agreement with published measured and simulated data.
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Affiliation(s)
- J Ramos-Méndez
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, United States of America. Author to whom any correspondence should be addressed
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Underwood TSA, Sung W, McFadden CH, McMahon SJ, Hall DC, McNamara AL, Paganetti H, Sawakuchi GO, Schuemann J. Comparing stochastic proton interactions simulated using TOPAS-nBio to experimental data from fluorescent nuclear track detectors. Phys Med Biol 2017; 62:3237-3249. [PMID: 28350546 PMCID: PMC8627280 DOI: 10.1088/1361-6560/aa6429] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [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] [Indexed: 12/12/2022]
Abstract
Whilst Monte Carlo (MC) simulations of proton energy deposition have been well-validated at the macroscopic level, their microscopic validation remains lacking. Equally, no gold-standard yet exists for experimental metrology of individual proton tracks. In this work we compare the distributions of stochastic proton interactions simulated using the TOPAS-nBio MC platform against confocal microscope data for Al2O3:C,Mg fluorescent nuclear track detectors (FNTDs). We irradiated [Formula: see text] mm3 FNTD chips inside a water phantom, positioned at seven positions along a pristine proton Bragg peak with a range in water of 12 cm. MC simulations were implemented in two stages: (1) using TOPAS to model the beam properties within a water phantom and (2) using TOPAS-nBio with Geant4-DNA physics to score particle interactions through a water surrogate of Al2O3:C,Mg. The measured median track integrated brightness (IB) was observed to be strongly correlated to both (i) voxelized track-averaged linear energy transfer (LET) and (ii) frequency mean microdosimetric lineal energy, [Formula: see text], both simulated in pure water. Histograms of FNTD track IB were compared against TOPAS-nBio histograms of the number of terminal electrons per proton, scored in water with mass-density scaled to mimic Al2O3:C,Mg. Trends between exposure depths observed in TOPAS-nBio simulations were experimentally replicated in the study of FNTD track IB. Our results represent an important first step towards the experimental validation of MC simulations on the sub-cellular scale and suggest that FNTDs can enable experimental study of the microdosimetric properties of individual proton tracks.
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Affiliation(s)
- T S A Underwood
- Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, United States of America. Department of Medical Engineering and Physics, University College London, London, United Kingdom
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McMahon SJ, McNamara AL, Schuemann J, Prise KM, Paganetti H. Mitochondria as a target for radiosensitisation by gold nanoparticles. ACTA ACUST UNITED AC 2017. [DOI: 10.1088/1742-6596/777/1/012008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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McNamara AL, Kam WWY, Scales N, McMahon SJ, Bennett JW, Byrne HL, Schuemann J, Paganetti H, Banati R, Kuncic Z. Dose enhancement effects to the nucleus and mitochondria from gold nanoparticles in the cytosol. Phys Med Biol 2016; 61:5993-6010. [PMID: 27435339 DOI: 10.1088/0031-9155/61/16/5993] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Gold nanoparticles (GNPs) have shown potential as dose enhancers for radiation therapy. Since damage to the genome affects the viability of a cell, it is generally assumed that GNPs have to localise within the cell nucleus. In practice, however, GNPs tend to localise in the cytoplasm yet still appear to have a dose enhancing effect on the cell. Whether this effect can be attributed to stress-induced biological mechanisms or to physical damage to extra-nuclear cellular targets is still unclear. There is however growing evidence to suggest that the cellular response to radiation can also be influenced by indirect processes induced when the nucleus is not directly targeted by radiation. The mitochondrion in particular may be an effective extra-nuclear radiation target given its many important functional roles in the cell. To more accurately predict the physical effect of radiation within different cell organelles, we measured the full chemical composition of a whole human lymphocytic JURKAT cell as well as two separate organelles; the cell nucleus and the mitochondrion. The experimental measurements found that all three biological materials had similar ionisation energies ∼70 eV, substantially lower than that of liquid water ∼78 eV. Monte Carlo simulations for 10-50 keV incident photons showed higher energy deposition and ionisation numbers in the cell and organelle materials compared to liquid water. Adding a 1% mass fraction of gold to each material increased the energy deposition by a factor of ∼1.8 when averaged over all incident photon energies. Simulations of a realistic compartmentalised cell show that the presence of gold in the cytosol increases the energy deposition in the mitochondrial volume more than within the nuclear volume. We find this is due to sub-micron delocalisation of energy by photoelectrons, making the mitochondria a potentially viable indirect radiation target for GNPs that localise to the cytosol.
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Affiliation(s)
- A L McNamara
- Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, 30 Fruit St, Boston, MA 02114, USA. School of Physics, University of Sydney, NSW 2006, Australia
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Abolfath R, Bronk L, Helo Y, Schuemann J, Titt U, Grosshans D, Mohan R. WE-H-BRA-01: BEST IN PHYSICS (THERAPY): Nano-Dosimetric Kinetic Model for Variable Relative Biological Effectiveness of Proton and Ion Beams. Med Phys 2016. [DOI: 10.1118/1.4957992] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Schuemann J. WE-DE-202-01: Connecting Nanoscale Physics to Initial DNA Damage Through Track Structure Simulations. Med Phys 2016. [DOI: 10.1118/1.4957842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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McMahon S, McNamara A, Schuemann J, Prise K, Paganetti H. WE-H-BRA-07: Mechanistic Modelling of the Relative Biological Effectiveness of Heavy Charged Particles. Med Phys 2016. [DOI: 10.1118/1.4957998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Marteinsdottir M, Schuemann J, Paganetti H. WE-AB-207B-06: Dose and Biological Uncertainties in Sarcoma. Med Phys 2016. [DOI: 10.1118/1.4957787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Oesten H, Loeck S, Helmbrecht S, Tillner F, Wohlfahrt P, Schuemann J, Luehr A. SU-F-T-682: In-Vivo Simulation of the Relative Biological Effectiveness in Proton Therapy Using a Monte Carlo Method. Med Phys 2016. [DOI: 10.1118/1.4956868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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McNamara A, Perl J, Piersimoni P, Ramos-Mendez J, Faddegon B, Held K, Paganetti H, Schuemann J. WE-H-BRA-04: Biological Geometries for the Monte Carlo Simulation Toolkit TOPASNBio. Med Phys 2016. [DOI: 10.1118/1.4957995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Hall D, Perl J, Schuemann J, Faddegon B, Paganetti H. SU-F-T-139: Meeting the Challenges of Quality Control in the TOPAS Monte Carlo Simulation Toolkit for Proton Therapy. Med Phys 2016. [DOI: 10.1118/1.4956275] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Geng C, Daartz J, Cheung K, Bussiere M, Shih H, Paganetti H, Schuemann J. SU-F-T-157: Physics Considerations Regarding Dosimetric Accuracy of Analytical Dose Calculations for Small Field Proton Therapy: A Monte Carlo Study. Med Phys 2016. [DOI: 10.1118/1.4956293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Underwood T, McFadden C, Trenholm D, Verburg J, Paganetti H, Sawakuchi G, Schuemann J. TH-CD-201-07: Experimentally Investigating Proton Energy Deposition On the Microscopic Scale Using Fluorescence Nuclear Track Detectors. Med Phys 2016. [DOI: 10.1118/1.4958129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Stewart R, Streitmatter S, Traneus E, Moskvin V, Schuemann J. MO-FG-CAMPUS-TeP3-02: Benchmarks of a Proton Relative Biological Effectiveness (RBE) Model for DNA Double Strand Break (DSB) Induction in the FLUKA, MCNP, TOPAS, and RayStation™ Treatment Planning System. Med Phys 2016. [DOI: 10.1118/1.4957382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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McNamara A, McMahon S, Lin Y, Paganetti H, Kuncic Z, Schuemann J. TU-F-CAMPUS-T-04: Using Gold Nanoparticles to Target Mitochondria in Radiation Therapy. Med Phys 2015. [DOI: 10.1118/1.4925819] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Lin Y, Held K, McMahon S, Paganetti H, Schuemann J. SU-E-T-518: Investigation of Gold Nanoparticle Radiosensitization for Carbon Ion Therapy. Med Phys 2015. [DOI: 10.1118/1.4924880] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Schuemann J, Giantsoudi D, Grassberger C, Paganetti H. SU-E-T-135: Assessing the Clinical Impact of Approximations in Analytical Dose Calculations for Proton Therapy. Med Phys 2015. [DOI: 10.1118/1.4924496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Geng C, Schuemann J, Moteabbed M, Paganetti H. SU-E-T-567: Neutron Dose Equivalent Evaluation for Pencil Beam Scanning Proton Therapy with Apertures. Med Phys 2015. [DOI: 10.1118/1.4924929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Qin N, Giantsoudi D, Tian Z, Schuemann J, Pompos A, Paganetti H, Jiang S, Jia X. SU-E-T-673: Recent Developments and Comprehensive Validations of a GPU-Based Proton Monte Carlo Simulation Package, GPMC. Med Phys 2015. [DOI: 10.1118/1.4925036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Ramos-Mendez J, Perl J, Schuemann J, Shin J, Paganetti H, Faddegon B. SU-E-T-466: Implementation of An Extension Module for Dose Response Models in the TOPAS Monte Carlo Toolkit. Med Phys 2015. [DOI: 10.1118/1.4924828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Toltz A, Hoesl M, Schuemann J, Seuntjens J, Lu H, Paganetti H. SU-E-T-524: In-Vivo Diode Dosimetry Proton Therapy Range Verification Validation Study for Pediatric CSI. Med Phys 2015. [DOI: 10.1118/1.4924886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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McNamara A, Schuemann J, Paganetti H. SU-F-BRD-13: A Phenomenological Relative Biological Effectiveness (RBE) Model for Proton Therapy Based On All Published in Vitro Cell Survival Data. Med Phys 2015. [DOI: 10.1118/1.4925192] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Hong X, Gao H, Schuemann J, Paganetti H. SU-E-T-769: T-Test Based Prior Error Estimate and Stopping Criterion for Monte Carlo Dose Calculation in Proton Therapy. Med Phys 2015. [DOI: 10.1118/1.4925133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Moteabbed M, Schuemann J, Paganetti H. Dosimetric feasibility of real-time MRI-guided proton therapy. Med Phys 2014; 41:111713. [PMID: 25370627 PMCID: PMC4209014 DOI: 10.1118/1.4897570] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [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: 04/09/2014] [Revised: 08/06/2014] [Accepted: 09/15/2014] [Indexed: 01/13/2023] Open
Abstract
PURPOSE Magnetic resonance imaging (MRI) is a prime candidate for image-guided radiotherapy. This study was designed to assess the feasibility of real-time MRI-guided proton therapy by quantifying the dosimetric effects induced by the magnetic field in patients' plans and identifying the associated clinical consequences. METHODS Monte Carlo dose calculation was performed for nine patients of various treatment sites (lung, liver, prostate, brain, skull-base, and spine) and tissue homogeneities, in the presence of 0.5 and 1.5 T magnetic fields. Dose volume histogram (DVH) parameters such as D95, D5, and V20 as well as equivalent uniform dose were compared for the target and organs at risk, before and after applying the magnetic field. The authors further assessed whether the plans affected by clinically relevant dose distortions could be corrected independent of the planning system. RESULTS By comparing the resulting dose distributions and analyzing the respective DVHs, it was determined that despite the observed lateral beam deflection, for magnetic fields of up to 0.5 T, neither was the target coverage jeopardized nor was the dose to the nearby organs increased in all cases except for prostate. However, for a 1.5 T magnetic field, the dose distortions were more pronounced and of clinical concern in all cases except for spine. In such circumstances, the target was severely underdosed, as indicated by a decrease in D95 of up to 41% of the prescribed dose compared to the nominal situation (no magnetic field). Sites such as liver and spine were less affected due to higher tissue homogeneity, typically smaller beam range, and the choice of beam directions. Simulations revealed that small modifications to certain plan parameters such as beam isocenter (up to 19 mm) and gantry angle (up to 10°) are sufficient to compensate for the magnetic field-induced dose disturbances. The authors' observations indicate that the degree of required corrections strongly depends on the beam range and direction relative to the magnetic field. This method was also applicable to more heterogeneous scenarios such as skull-base tumors. CONCLUSIONS This study confirmed the dosimetric feasibility of real-time MRI-guided proton therapy and delivering a clinically acceptable dose to patients with various tumor locations within magnetic fields of up to 1.5 T. This work could serve as a guide and encouragement for further efforts toward clinical implementation of hybrid MRI-proton gantry systems.
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Affiliation(s)
- M Moteabbed
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
| | - J Schuemann
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
| | - H Paganetti
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114
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Abe K, Hayato Y, Iida T, Iyogi K, Kameda J, Koshio Y, Kozuma Y, Marti L, Miura M, Moriyama S, Nakahata M, Nakayama S, Obayashi Y, Sekiya H, Shiozawa M, Suzuki Y, Takeda A, Takenaga Y, Ueno K, Ueshima K, Yamada S, Yokozawa T, Ishihara C, Kaji H, Kajita T, Kaneyuki K, Lee KP, McLachlan T, Okumura K, Shimizu Y, Tanimoto N, Labarga L, Kearns E, Litos M, Raaf JL, Stone JL, Sulak LR, Goldhaber M, Bays K, Kropp WR, Mine S, Regis C, Renshaw A, Smy MB, Sobel HW, Ganezer KS, Hill J, Keig WE, Jang JS, Kim JY, Lim IT, Albert JB, Scholberg K, Walter CW, Wendell R, Wongjirad TM, Ishizuka T, Tasaka S, Learned JG, Matsuno S, Smith SN, Hasegawa T, Ishida T, Ishii T, Kobayashi T, Nakadaira T, Nakamura K, Nishikawa K, Oyama Y, Sakashita K, Sekiguchi T, Tsukamoto T, Suzuki AT, Takeuchi Y, Ikeda M, Minamino A, Nakaya T, Fukuda Y, Itow Y, Mitsuka G, Tanaka T, Jung CK, Lopez GD, Taylor I, Yanagisawa C, Ishino H, Kibayashi A, Mino S, Mori T, Sakuda M, Toyota H, Kuno Y, Yoshida M, Kim SB, Yang BS, Okazawa H, Choi Y, Nishijima K, Koshiba M, Yokoyama M, Totsuka Y, Martens K, Schuemann J, Vagins MR, Chen S, Heng Y, Yang Z, Zhang H, Kielczewska D, Mijakowski P, Connolly K, Dziomba M, Thrane E, Wilkes RJ. Search for nucleon decay via n→ν[over ¯]π0 and p→ν[over ¯]π+ in Super-Kamiokande. Phys Rev Lett 2014; 113:121802. [PMID: 25279622 DOI: 10.1103/physrevlett.113.121802] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Indexed: 06/03/2023]
Abstract
We present the results of searches for nucleon decay via n→ν[over ¯]π0 and p→ν[over ¯]π+ using data from a combined 172.8 kt·yr exposure of Super-Kamiokande-I,-II, and-III. We set lower limits on the partial lifetime for each of these modes: τn→ν[over ¯]π0>1.1×10(33) years and τp→ν[over ¯]π+>3.9×10(32) years at a 90% confidence level.
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Affiliation(s)
- K Abe
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - Y Hayato
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - T Iida
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan
| | - K Iyogi
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan
| | - J Kameda
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - Y Koshio
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - Y Kozuma
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan
| | - Ll Marti
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan
| | - M Miura
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - S Moriyama
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - M Nakahata
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - S Nakayama
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - Y Obayashi
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - H Sekiya
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - M Shiozawa
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - Y Suzuki
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - A Takeda
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - Y Takenaga
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan
| | - K Ueno
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan
| | - K Ueshima
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan
| | - S Yamada
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan
| | - T Yokozawa
- Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan
| | - C Ishihara
- Research Center for Cosmic Neutrinos, Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582, Japan
| | - H Kaji
- Research Center for Cosmic Neutrinos, Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582, Japan
| | - T Kajita
- Research Center for Cosmic Neutrinos, Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - K Kaneyuki
- Research Center for Cosmic Neutrinos, Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - K P Lee
- Research Center for Cosmic Neutrinos, Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582, Japan
| | - T McLachlan
- Research Center for Cosmic Neutrinos, Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582, Japan
| | - K Okumura
- Research Center for Cosmic Neutrinos, Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582, Japan
| | - Y Shimizu
- Research Center for Cosmic Neutrinos, Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582, Japan
| | - N Tanimoto
- Research Center for Cosmic Neutrinos, Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582, Japan
| | - L Labarga
- Department of Theoretical Physics, University Autonoma Madrid, 28049 Madrid, Spain
| | - E Kearns
- Department of Physics, Boston University, Boston, Massachusetts 02215, USA and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - M Litos
- Department of Physics, Boston University, Boston, Massachusetts 02215, USA
| | - J L Raaf
- Department of Physics, Boston University, Boston, Massachusetts 02215, USA
| | - J L Stone
- Department of Physics, Boston University, Boston, Massachusetts 02215, USA and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - L R Sulak
- Department of Physics, Boston University, Boston, Massachusetts 02215, USA
| | - M Goldhaber
- Physics Department, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - K Bays
- Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697-4575, USA
| | - W R Kropp
- Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697-4575, USA
| | - S Mine
- Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697-4575, USA
| | - C Regis
- Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697-4575, USA
| | - A Renshaw
- Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697-4575, USA
| | - M B Smy
- Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697-4575, USA and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - H W Sobel
- Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697-4575, USA and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - K S Ganezer
- Department of Physics, California State University, Dominguez Hills, Carson, California 90747, USA
| | - J Hill
- Department of Physics, California State University, Dominguez Hills, Carson, California 90747, USA
| | - W E Keig
- Department of Physics, California State University, Dominguez Hills, Carson, California 90747, USA
| | - J S Jang
- Department of Physics, Chonnam National University, Kwangju 500-757, Korea
| | - J Y Kim
- Department of Physics, Chonnam National University, Kwangju 500-757, Korea
| | - I T Lim
- Department of Physics, Chonnam National University, Kwangju 500-757, Korea
| | - J B Albert
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - K Scholberg
- Department of Physics, Duke University, Durham, North Carolina 27708, USA and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - C W Walter
- Department of Physics, Duke University, Durham, North Carolina 27708, USA and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - R Wendell
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - T M Wongjirad
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - T Ishizuka
- Junior College, Fukuoka Institute of Technology, Fukuoka 811-0214, Japan
| | - S Tasaka
- Information and Multimedia Center, Gifu University, Gifu, Gifu 501-1193, Japan
| | - J G Learned
- Department of Physics and Astronomy, University of Hawaii, Honolulu, Hawaii 96822, USA
| | - S Matsuno
- Department of Physics and Astronomy, University of Hawaii, Honolulu, Hawaii 96822, USA
| | - S N Smith
- Department of Physics and Astronomy, University of Hawaii, Honolulu, Hawaii 96822, USA
| | - T Hasegawa
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - T Ishida
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - T Ishii
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - T Kobayashi
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - T Nakadaira
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - K Nakamura
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - K Nishikawa
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - Y Oyama
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - K Sakashita
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - T Sekiguchi
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - T Tsukamoto
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - A T Suzuki
- Department of Physics, Kobe University, Kobe, Hyogo 657-8501, Japan
| | - Y Takeuchi
- Department of Physics, Kobe University, Kobe, Hyogo 657-8501, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - M Ikeda
- Department of Physics, Kyoto University, Kyoto, Kyoto 606-8502, Japan
| | - A Minamino
- Department of Physics, Kyoto University, Kyoto, Kyoto 606-8502, Japan
| | - T Nakaya
- Department of Physics, Kyoto University, Kyoto, Kyoto 606-8502, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - Y Fukuda
- Department of Physics, Miyagi University of Education, Sendai, Miyagi 980-0845, Japan
| | - Y Itow
- Solar Terrestrial Environment Laboratory, Nagoya University, Nagoya, Aichi 464-8602, Japan and Kobayashi-Maskawa Institute for the Origin of Particles and the Universe, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - G Mitsuka
- Solar Terrestrial Environment Laboratory, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - T Tanaka
- Solar Terrestrial Environment Laboratory, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - C K Jung
- Department of Physics and Astronomy, State University of New York, Stony Brook, New York 11794-3800, USA
| | - G D Lopez
- Department of Physics and Astronomy, State University of New York, Stony Brook, New York 11794-3800, USA
| | - I Taylor
- Department of Physics and Astronomy, State University of New York, Stony Brook, New York 11794-3800, USA
| | - C Yanagisawa
- Department of Physics and Astronomy, State University of New York, Stony Brook, New York 11794-3800, USA
| | - H Ishino
- Department of Physics, Okayama University, Okayama, Okayama 700-8530, Japan
| | - A Kibayashi
- Department of Physics, Okayama University, Okayama, Okayama 700-8530, Japan
| | - S Mino
- Department of Physics, Okayama University, Okayama, Okayama 700-8530, Japan
| | - T Mori
- Department of Physics, Okayama University, Okayama, Okayama 700-8530, Japan
| | - M Sakuda
- Department of Physics, Okayama University, Okayama, Okayama 700-8530, Japan
| | - H Toyota
- Department of Physics, Okayama University, Okayama, Okayama 700-8530, Japan
| | - Y Kuno
- Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - M Yoshida
- Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - S B Kim
- Department of Physics, Seoul National University, Seoul 151-742, Korea
| | - B S Yang
- Department of Physics, Seoul National University, Seoul 151-742, Korea
| | - H Okazawa
- Department of Informatics in Social Welfare, Shizuoka University of Welfare, Yaizu, Shizuoka, 425-8611, Japan
| | - Y Choi
- Department of Physics, Sungkyunkwan University, Suwon 440-746, Korea
| | - K Nishijima
- Department of Physics, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan
| | - M Koshiba
- The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - M Yokoyama
- The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - Y Totsuka
- The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - K Martens
- Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - J Schuemann
- Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - M R Vagins
- Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697-4575, USA and Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - S Chen
- Department of Engineering Physics, Tsinghua University, Beijing 100084, China
| | - Y Heng
- Department of Engineering Physics, Tsinghua University, Beijing 100084, China
| | - Z Yang
- Department of Engineering Physics, Tsinghua University, Beijing 100084, China
| | - H Zhang
- Department of Engineering Physics, Tsinghua University, Beijing 100084, China
| | - D Kielczewska
- Institute of Experimental Physics, Warsaw University, 00-681 Warsaw, Poland
| | - P Mijakowski
- Institute of Experimental Physics, Warsaw University, 00-681 Warsaw, Poland
| | - K Connolly
- Department of Physics, University of Washington, Seattle, Washington 98195-1560, USA
| | - M Dziomba
- Department of Physics, University of Washington, Seattle, Washington 98195-1560, USA
| | - E Thrane
- Department of Physics, University of Washington, Seattle, Washington 98195-1560, USA
| | - R J Wilkes
- Department of Physics, University of Washington, Seattle, Washington 98195-1560, USA
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Schuemann J, Dowdell S, Grassberger C, Min CH, Paganetti H. Site-specific range uncertainties caused by dose calculation algorithms for proton therapy. Phys Med Biol 2014; 59:4007-31. [PMID: 24990623 DOI: 10.1088/0031-9155/59/15/4007] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The purpose of this study was to assess the possibility of introducing site-specific range margins to replace current generic margins in proton therapy. Further, the goal was to study the potential of reducing margins with current analytical dose calculations methods. For this purpose we investigate the impact of complex patient geometries on the capability of analytical dose calculation algorithms to accurately predict the range of proton fields. Dose distributions predicted by an analytical pencil-beam algorithm were compared with those obtained using Monte Carlo (MC) simulations (TOPAS). A total of 508 passively scattered treatment fields were analyzed for seven disease sites (liver, prostate, breast, medulloblastoma-spine, medulloblastoma-whole brain, lung and head and neck). Voxel-by-voxel comparisons were performed on two-dimensional distal dose surfaces calculated by pencil-beam and MC algorithms to obtain the average range differences and root mean square deviation for each field for the distal position of the 90% dose level (R90) and the 50% dose level (R50). The average dose degradation of the distal falloff region, defined as the distance between the distal position of the 80% and 20% dose levels (R80-R20), was also analyzed. All ranges were calculated in water-equivalent distances. Considering total range uncertainties and uncertainties from dose calculation alone, we were able to deduce site-specific estimations. For liver, prostate and whole brain fields our results demonstrate that a reduction of currently used uncertainty margins is feasible even without introducing MC dose calculations. We recommend range margins of 2.8% + 1.2 mm for liver and prostate treatments and 3.1% + 1.2 mm for whole brain treatments, respectively. On the other hand, current margins seem to be insufficient for some breast, lung and head and neck patients, at least if used generically. If no case specific adjustments are applied, a generic margin of 6.3% + 1.2 mm would be needed for breast, lung and head and neck treatments. We conclude that the currently used generic range uncertainty margins in proton therapy should be redefined site specific and that complex geometries may require a field specific adjustment. Routine verifications of treatment plans using MC simulations are recommended for patients with heterogeneous geometries.
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Affiliation(s)
- J Schuemann
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
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Lin Y, Paganetti H, Schuemann J. WE-G-BRE-04: Gold Nanoparticle Induced Vasculature Damage for Proton Therapy: Monte Carlo Simulation. Med Phys 2014. [DOI: 10.1118/1.4889479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Lin Y, Paganetti H, Schuemann J. WE-G-BRE-02: Biological Modeling of Gold Nanoparticle Radiosensitization for Proton Therapy. Med Phys 2014. [DOI: 10.1118/1.4889477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Dowdell S, Greilich S, Zimmerman F, Evans C, Paganetti H, Schuemann J. WE-D-BRF-01: FEATURED PRESENTATION - Investigating Particle Track Structures Using Fluorescent Nuclear Track Detectors and Monte Carlo Simulations. Med Phys 2014. [DOI: 10.1118/1.4889399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Schuemann J, Dowdell S, Grassberger C, Paganetti H. TH-A-19A-06: Site-Specific Comparison of Analytical and Monte Carlo Based Dose Calculations. Med Phys 2014. [DOI: 10.1118/1.4889539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Schuemann J, Giantsoudi D, Rinaldi I, Perl J, Faddegon B, Paganetti H. TH-A-19A-02: Expanding TOPAS Towards Biological Modeling. Med Phys 2014. [DOI: 10.1118/1.4889535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Giantsoudi D, Schuemann J, Dowdell S, Jia X, Jiang S, Paganetti H. TH-A-19A-11: Validation of GPU-Based Monte Carlo Code (gPMC) Versus Fully Implemented Monte Carlo Code (TOPAS) for Proton Radiation Therapy: Clinical Cases Study. Med Phys 2014. [DOI: 10.1118/1.4889544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Sorriaux J, Paganetti H, Testa M, Giantsoudi D, Schuemann J, Bertrand D, Orban de Xivry J, Lee J, Palmans H, Vynckier S, Sterpin E. SU-E-T-464: On the Equivalence of the Quality Correction Factor for Pencil Beam Scanning Proton Therapy. Med Phys 2014. [DOI: 10.1118/1.4888797] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Sterpin E, Sorriaux J, Schuemann J, Souris K, Lee J, Vynckier S, Jia X, Jiang S, Paganetti H. SU-E-T-180: Fano Cavity Test of Proton Transport in Monte Carlo Codes Running On GPU and Xeon Phi. Med Phys 2014. [DOI: 10.1118/1.4888510] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Bueno M, Paganetti H, Duch MA, Schuemann J. An algorithm to assess the need for clinical Monte Carlo dose calculation for small proton therapy fields based on quantification of tissue heterogeneity. Med Phys 2014; 40:081704. [PMID: 23927301 DOI: 10.1118/1.4812682] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
PURPOSE In proton therapy, complex density heterogeneities within the beam path constitute a challenge to dose calculation algorithms. This might question the reliability of dose distributions predicted by treatment planning systems based on analytical dose calculation. For cases in which substantial dose errors are expected, resorting to Monte Carlo dose calculations might be essential to ensure a successful treatment outcome and therefore the benefit is worth a presumably long computation time. The aim of this study was to define an indicator for the accuracy of dose delivery based on analytical dose calculations in treatment planning systems for small proton therapy fields to identify those patients for which Monte Carlo dose calculation is warranted. METHODS Fourteen patients treated at our facility with small passively scattered proton beams (apertures diameters below 7 cm) were selected. Plans were generated in the XiO treatment planning system in combination with a pencil beam algorithm developed at the Massachusetts General Hospital and compared to Monte Carlo dose calculations. Differences in the dose to the 50% of the gross tumor volume (D50, GTV) were assessed in a field-by-field basis. A simple and fast methodology was developed to quantify the inhomogeneity of the tissue traversed by a single small proton beam using a heterogeneity index (HI)-a concept presented by Plugfelder et al. [Med. Phys. 34, 1506-1513 (2007)] for scanned proton beams. Finally, the potential correlation between the error made by the pencil beam based treatment planning algorithm for each field and the level of tissue heterogeneity traversed by the proton beam given by the HI was evaluated. RESULTS Discrepancies up to 5.4% were found in D50 for single fields, although dose differences were within clinical tolerance levels (<3%) when combining all of the fields involved in the treatment. The discrepancies found for each field exhibited a strong correlation to their associated HI-values (Spearman's ρ=0.8, p<0.0001); the higher the level of tissue inhomogeneities for a particular field, the larger the error by the analytical algorithm. With the established correlation a threshold for HI can be set by choosing a tolerance level of 2-3%-commonly accepted in radiotherapy. CONCLUSIONS The HI is a good indicator for the accuracy of proton field delivery in terms of GTV prescription dose coverage when small fields are delivered. Each HI-value was obtained from the CT image in less than 3 min on a computer with 2 GHz CPU allowing implementation of this methodology in clinical routine. For HI-values exceeding the threshold, either a change in beam direction (if feasible) or a recalculation of the dose with Monte Carlo would be highly recommended.
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Affiliation(s)
- M Bueno
- Departament de Dosimetria i Física Mèdica, Institut de Tècniques Energètiques, Universitat Politècnica de Catalunya, 08028 Barcelona, Spain.
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Lin Y, Paganetti H, Schuemann J. OC-0079: Biological modeling of gold nanoparticle radiosensitization for proton therapy. Radiother Oncol 2014. [DOI: 10.1016/s0167-8140(15)30184-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Lin Y, Scarpelli M, Paganetti H, Schuemann J. PD-0096: Quantification of gold nanoparticle induced microscopic dose enhancement using protons. Radiother Oncol 2014. [DOI: 10.1016/s0167-8140(15)30201-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Schuemann J, Testa M, Bueno M, Min C, Moteabbed M, Giantsoudi D, Paganetti H. SU-E-T-451: Patient and Site-Specific Assessment of the Value of Routine Monte Carlo Dose Calculation in Proton Therapy. Med Phys 2013. [DOI: 10.1118/1.4814884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Schuemann J, Dowdell S, Barbone G, Paganetti H. SU-E-T-404: Quantification of Proton Dose Enhancement Resulting From Gold Nanoparticles. Med Phys 2013. [DOI: 10.1118/1.4814838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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