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Raturi VP, Hojo H, Hotta K, Baba H, Takahashi R, Rachi T, Nakamura N, Zenda S, Motegi A, Tachibana H, Ariji T, Motegi K, Nakamura M, Okumura M, Hirano Y, Akimoto T. Radiobiological model-based approach to determine the potential of dose-escalated robust intensity-modulated proton radiotherapy in reducing gastrointestinal toxicity in the treatment of locally advanced unresectable pancreatic cancer of the head. Radiat Oncol 2020; 15:157. [PMID: 32571379 PMCID: PMC7310413 DOI: 10.1186/s13014-020-01592-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 06/03/2020] [Indexed: 12/31/2022] Open
Abstract
Background The purpose of this study was to determine the potential of escalated dose radiation (EDR) robust intensity-modulated proton radiotherapy (ro-IMPT) in reducing GI toxicity risk in locally advanced unresectable pancreatic cancer (LAUPC) of the head in term of normal tissue complication probability (NTCP) predictive model. Methods For 9 patients, intensity-modulated radiotherapy (IMRT) was compared with ro-IMPT. For all plans, the prescription dose was 59.4GyE (Gray equivalent) in 33 fractions with an equivalent organ at risk (OAR) constraints. Physical dose distribution was evaluated. GI toxicity risk for different endpoints was estimated using published NTCP Lyman Kutcher Burman (LKB) models for stomach, duodenum, small bowel, and combine stomach and duodenum (Stoduo). A Wilcoxon signed-rank test was used for dosimetry parameters and NTCP values comparison. Result The dosimetric results have shown that, with similar target coverage, ro-IMPT achieves a significant dose-volume reduction in the stomach, small bowel, and stoduo in low to high dose range in comparison to IMRT. NTCP evaluation for the endpoint gastric bleeding of stomach (10.55% vs. 13.97%, P = 0.007), duodenum (1.87% vs. 5.02%, P = 0.004), and stoduo (5.67% vs. 7.81%, P = 0.008) suggest reduced toxicity by ro-IMPT compared to IMRT. ∆NTCP IMRT – ro-IMPT (using parameter from Pan et al. for gastric bleed) of ≥5 to < 10% was seen in 3 patients (33%) for stomach and 2 patients (22%) for stoduo. An overall GI toxicity relative risk (NTCPro-IMPT/NTCPIMRT) reduction was noted (0.16–0.81) for all GI-OARs except for duodenum (> 1) with endpoint grade ≥ 3 GI toxicity (using parameters from Holyoake et al.). Conclusion With similar target coverage and better conformity, ro-IMPT has the potential to substantially reduce the risk of GI toxicity compared to IMRT in EDR of LAUPC of the head. This result needs to be further evaluated in future clinical studies.
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Affiliation(s)
- Vijay P Raturi
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan.,Course of Advanced Clinical Research of Cancer, Graduate school of Medicine, Juntendo University, Tokyo, Japan
| | - Hidehiro Hojo
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan
| | - Kenji Hotta
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan
| | - Hiromi Baba
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan
| | - Ryo Takahashi
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan
| | - Toshiya Rachi
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan
| | - Naoki Nakamura
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan
| | - Sadamoto Zenda
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan
| | - Atsushi Motegi
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan
| | - Hidenobu Tachibana
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan
| | - Takaki Ariji
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan
| | - Kana Motegi
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan
| | - Masaki Nakamura
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan
| | - Masayuki Okumura
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan
| | - Yasuhiro Hirano
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan
| | - Tetsuo Akimoto
- Division of Radiation Oncology and Particle therapy, National Cancer Center Hospital East, 6-5-1 chome, Kashiwanoha, Kashiwa-shi, Chiba-ken, 277-8577, Japan. .,Course of Advanced Clinical Research of Cancer, Graduate school of Medicine, Juntendo University, Tokyo, Japan.
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2
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Raturi VP, Tochinai T, Hojo H, Rachi T, Hotta K, Nakamura N, Zenda S, Motegi A, Ariji T, Hirano Y, Baba H, Ohyoshi H, Nakamura M, Okumura M, Bei Y, Akimoto T. Dose-Volume and Radiobiological Model-Based Comparative Evaluation of the Gastrointestinal Toxicity Risk of Photon and Proton Irradiation Plans in Localized Pancreatic Cancer Without Distant Metastasis. Front Oncol 2020; 10:517061. [PMID: 33194580 PMCID: PMC7645056 DOI: 10.3389/fonc.2020.517061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 09/01/2020] [Indexed: 12/25/2022] Open
Abstract
Background: Radiobiological model-based studies of photon-modulated radiotherapy for pancreatic cancer have reported reduced gastrointestinal (GI) toxicity, although the risk is still high. The purpose of this study was to investigate the potential of 3D-passive scattering proton beam therapy (3D-PSPBT) in limiting GI organ at risk (OAR) toxicity in localized pancreatic cancer based on dosimetric data and the normal tissue complication probability (NTCP) model. Methods: The data of 24 pancreatic cancer patients were retrospectively analyzed, and these patients were planned with intensity-modulated radiotherapy (IMRT), volume-modulated arc therapy (VMAT), and 3D-PSPBT. The tumor was targeted without elective nodal coverage. All generated plans consisted of a 50.4-GyE (Gray equivalent) dose in 28 fractions with equivalent OAR constraints, and they were normalized to cover 50% of the planning treatment volume (PTV) with 100% of the prescription dose. Physical dose distributions were evaluated. GI-OAR toxicity risk for different endpoints was estimated by using published NTCP Lyman-Kutcher-Burman (LKB) models. Analysis of variance (ANOVA) was performed to compare the dosimetric data, and ΔNTCPIMRT-PSPBT and ΔNTCPVMAT-PSPBT were also computed. Results: Similar homogeneity and conformity for the clinical target volume (CTV) and PTV were exhibited by all three planning techniques (P > 0.05). 3D-PSPBT resulted in a significant dose reduction for GI-OARs in both the low-intermediate dose range (below 30 GyE) and the highest dose region (D max and V 50 GyE) in comparison with IMRT and VMAT (P < 0.05). Based on the NTCP evaluation, the NTCP reduction for GI-OARs by 3D-PSPBT was minimal in comparison with IMRT and VMAT. Conclusion: 3D-PSPBT results in minimal NTCP reduction and has less potential to substantially reduce the toxicity risk of upper GI bleeding, ulceration, obstruction, and perforation endpoints compared to IMRT and VMAT. 3D-PSPBT may have the potential to reduce acute dose-limiting toxicity in the form of nausea, vomiting, and diarrhea by reducing the GI-OAR treated volume in the low-to-intermediate dose range. However, this result needs to be further evaluated in future clinical studies.
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Affiliation(s)
- Vijay P. Raturi
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
- Course of Advanced Clinical Research of Cancer, Graduate School of Medicine, Juntendo University, Tokyo, Japan
- *Correspondence: Vijay P. Raturi
| | - Taku Tochinai
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
| | - Hidehiro Hojo
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
| | - Toshiya Rachi
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
| | - Kenji Hotta
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
| | - Naoki Nakamura
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
| | - Sadamoto Zenda
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
| | - Atsushi Motegi
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
| | - Takaki Ariji
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
| | - Yasuhiro Hirano
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
| | - Hiromi Baba
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
| | - Hajime Ohyoshi
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
| | - Masaki Nakamura
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
| | - Masayuki Okumura
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
| | - Yanping Bei
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
| | - Tetsuo Akimoto
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital, Chiba, Japan
- Course of Advanced Clinical Research of Cancer, Graduate School of Medicine, Juntendo University, Tokyo, Japan
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Paganetti H, Blakely E, Carabe-Fernandez A, Carlson DJ, Das IJ, Dong L, Grosshans D, Held KD, Mohan R, Moiseenko V, Niemierko A, Stewart RD, Willers H. Report of the AAPM TG-256 on the relative biological effectiveness of proton beams in radiation therapy. Med Phys 2019; 46:e53-e78. [PMID: 30661238 DOI: 10.1002/mp.13390] [Citation(s) in RCA: 182] [Impact Index Per Article: 36.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 11/21/2018] [Accepted: 01/13/2019] [Indexed: 12/14/2022] Open
Abstract
The biological effectiveness of proton beams relative to photon beams in radiation therapy has been taken to be 1.1 throughout the history of proton therapy. While potentially appropriate as an average value, actual relative biological effectiveness (RBE) values may differ. This Task Group report outlines the basic concepts of RBE as well as the biophysical interpretation and mathematical concepts. The current knowledge on RBE variations is reviewed and discussed in the context of the current clinical use of RBE and the clinical relevance of RBE variations (with respect to physical as well as biological parameters). The following task group aims were designed to guide the current clinical practice: Assess whether the current clinical practice of using a constant RBE for protons should be revised or maintained. Identifying sites and treatment strategies where variable RBE might be utilized for a clinical benefit. Assess the potential clinical consequences of delivering biologically weighted proton doses based on variable RBE and/or LET models implemented in treatment planning systems. Recommend experiments needed to improve our current understanding of the relationships among in vitro, in vivo, and clinical RBE, and the research required to develop models. Develop recommendations to minimize the effects of uncertainties associated with proton RBE for well-defined tumor types and critical structures.
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Affiliation(s)
- Harald Paganetti
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Eleanor Blakely
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | | | - David J Carlson
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT, USA
| | - Indra J Das
- New York University Langone Medical Center & Laura and Isaac Perlmutter Cancer Center, New York, NY, USA
| | - Lei Dong
- Department of Radiation Oncology, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - David Grosshans
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Kathryn D Held
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Radhe Mohan
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Vitali Moiseenko
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA, USA
| | - Andrzej Niemierko
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Robert D Stewart
- Department of Radiation Oncology, School of Medicine, University of Washington, Seattle, WA, USA
| | - Henning Willers
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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4
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Szabó ER, Brand M, Hans S, Hideghéty K, Karsch L, Lessmann E, Pawelke J, Schürer M, Beyreuther E. Radiobiological effects and proton RBE determined by wildtype zebrafish embryos. PLoS One 2018; 13:e0206879. [PMID: 30408095 PMCID: PMC6224071 DOI: 10.1371/journal.pone.0206879] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 10/22/2018] [Indexed: 12/16/2022] Open
Abstract
The increasing use of proton radiotherapy during the last decade and the rising number of long-term survivors has given rise to a vital discussion on potential effects on normal tissue. So far, deviations from clinically applied generic RBE (relative biological effectiveness) of 1.1 were only obtained by in vitro studies, whereas indications from in vivo trials and clinical studies are rare. In the present work, wildtype zebrafish embryos (Danio rerio) were used to characterize the effects of plateau and mid-SOBP (spread-out Bragg peak) proton radiation relative to that induced by clinical MV photon beam reference. Based on embryonic survival data, RBE values of 1.13 ± 0.08 and of 1.20 ± 0.04 were determined four days after irradiations with 20 Gy plateau and SOBP protons relative to 6 MV photon beams. These RBE values were confirmed by relating the rates of embryos with morphological abnormalities for the respective radiation qualities and doses. Besides survival, the rate of spine bending, as one type of developmental abnormality, and of pericardial edema, as an example for acute radiation effects, were assessed. The results revealed that independent on radiation quality both rates increased with time approaching almost 100% at the 4th day post irradiation with doses higher than 15 Gy. To sum up, the applicability of the zebrafish embryo as a robust and simple alternative model for in vivo characterization of radiobiological effects in normal tissue was validated and the obtained RBE values are comparable to previous finding in animal trials.
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Affiliation(s)
- Emília Rita Szabó
- Attosecond Light Pulse Source, ELI-HU Nonprofit Ltd., Szeged, Hungary
| | - Michael Brand
- Center for Molecular and Cellular Bioengeneering (CMCB), DFG-Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany
| | - Stefan Hans
- Center for Molecular and Cellular Bioengeneering (CMCB), DFG-Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany
| | - Katalin Hideghéty
- Attosecond Light Pulse Source, ELI-HU Nonprofit Ltd., Szeged, Hungary
| | - Leonhard Karsch
- Helmholtz-Zentrum Dresden – Rossendorf, Dresden, Germany
- OncoRay – National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany
| | - Elisabeth Lessmann
- OncoRay – National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany
| | - Jörg Pawelke
- Helmholtz-Zentrum Dresden – Rossendorf, Dresden, Germany
- OncoRay – National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany
| | - Michael Schürer
- OncoRay – National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany
- National Center for Tumor Diseases (NCT), partner site Dresden, Germany
| | - Elke Beyreuther
- Helmholtz-Zentrum Dresden – Rossendorf, Dresden, Germany
- OncoRay – National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany
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5
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Szabó ER, Reisz Z, Polanek R, Tőkés T, Czifrus S, Pesznyák C, Biró B, Fenyvesi A, Király B, Molnár J, Brunner S, Daroczi B, Varga Z, Hideghéty K. A novel vertebrate system for the examination and direct comparison of the relative biological effectiveness for different radiation qualities and sources. Int J Radiat Biol 2018; 94:985-995. [PMID: 30332320 DOI: 10.1080/09553002.2018.1511928] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
PURPOSE The recent rapid increase of hadron therapy applications requires the development of high performance, reliable in vivo models for preclinical research on the biological effects of high linear energy transfer (LET) particle radiation. AIM The aim of this paper was to test the relative biological effectiveness (RBE) of the zebrafish embryo system at two neutron facilities. MATERIAL AND METHODS Series of viable zebrafish embryos at 24-hour post-fertilization (hpf) were exposed to single fraction, whole-body, photon and neutron (reactor fission neutrons (<En = 1 MeV>) and (p (18 MeV)+Be, <En> = 3.5 MeV) fast neutron) irradiation. The survival and morphologic abnormalities of each embryo were assessed at 24-hour intervals from the point of fertilization up to 192 hpf and then compared to conventional 6 MV photon beam irradiation results. RESULTS The higher energy of the fast neutron beams represents lower RBE (ref. source LINAC 6 MV photon). The lethality rate in the zebrafish embryo model was 10 times higher for 1 MeV fission neutrons and 2.5 times greater for p (18 MeV)+Be cyclotron generated fast neutron beam when compared to photon irradiation results. Dose-dependent organ perturbations (shortening of the body length, spine curvature, microcephaly, micro-ophthalmia, pericardial edema and inhibition of yolk sac resorption) and microscopic (marked cellular changes in eyes, brain, liver, muscle and the gastrointestinal system) changes scale together with the dose response. CONCLUSION The zebrafish embryo system is a powerful and versatile model for assessing the effect of ionizing radiation with different LET values on viability, organ and tissue development.
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Affiliation(s)
- E R Szabó
- a Extreme Light Infrastructure - Attosecond Light Pulse Source, ELI-HU Non-Profit Ltd , Szeged , Hungary
| | - Z Reisz
- b Department of Pathology , University of Szeged , Szeged , Hungary
| | - R Polanek
- a Extreme Light Infrastructure - Attosecond Light Pulse Source, ELI-HU Non-Profit Ltd , Szeged , Hungary
| | - T Tőkés
- a Extreme Light Infrastructure - Attosecond Light Pulse Source, ELI-HU Non-Profit Ltd , Szeged , Hungary
| | - Sz Czifrus
- c Budapest University of Technology and Economics Institute of Nuclear Techniques , Budapest , Hungary
| | - Cs Pesznyák
- c Budapest University of Technology and Economics Institute of Nuclear Techniques , Budapest , Hungary
| | - B Biró
- d Hungarian Academy of Sciences Institute for Nuclear Research (MTA Atomki) , Debrecen , Hungary
| | - A Fenyvesi
- d Hungarian Academy of Sciences Institute for Nuclear Research (MTA Atomki) , Debrecen , Hungary
| | - B Király
- d Hungarian Academy of Sciences Institute for Nuclear Research (MTA Atomki) , Debrecen , Hungary
| | - J Molnár
- d Hungarian Academy of Sciences Institute for Nuclear Research (MTA Atomki) , Debrecen , Hungary
| | - Sz Brunner
- a Extreme Light Infrastructure - Attosecond Light Pulse Source, ELI-HU Non-Profit Ltd , Szeged , Hungary
| | - B Daroczi
- e Department of Internal Medicine, Division of Geriatrics , University of Debrecen , Debrecen , Hungary
| | - Z Varga
- f Department of Oncotherapy , University of Szeged , Szeged , Hungary
| | - K Hideghéty
- a Extreme Light Infrastructure - Attosecond Light Pulse Source, ELI-HU Non-Profit Ltd , Szeged , Hungary.,f Department of Oncotherapy , University of Szeged , Szeged , Hungary
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6
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Grün R, Friedrich T, Krämer M, Scholz M. Systematics of relative biological effectiveness measurements for proton radiation along the spread out Bragg peak: experimental validation of the local effect model. Phys Med Biol 2017; 62:890-908. [PMID: 28072575 DOI: 10.1088/1361-6560/62/3/890] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The purpose of this study is to compare the predictions of the local effect model (LEM) in an extensive analysis to proton relative biological effectiveness (RBE) experiments found in the literature, and demonstrate the capabilities of the model as well as to discuss potential limitations. 19 publications with in vitro experiments and 10 publications with in vivo experiments focusing on proton RBE along the spread out Bragg peak (SOBP) were considered. In total the RBE values of over 100 depth positions were compared to LEM predictions. The treatment planning software TRiP98 was used to reconstruct the proton depth dose profile, and, together with the physical dose distribution, the RBE prediction was conducted based on the LEM. Only parameters from photon dose response curves are used as input for the LEM, and no free parameters are introduced, thus allowing us to demonstrate the predictive power of the LEM for protons. The LEM describes the RBE adequately well within the SOBP region with a relative deviation of typically less than 10% up to 10 keV µm-1. In accordance with previous publications a clear dependence of RBE on the dose-averaged linear energy transfer (LETD) was observed. The RBE in the experiments tends to increase above 1.1 for LETD values above 2 keV µm-1 and above 1.5 for LETD values higher than 10 keV µm-1 (distal part of the SOBP). The dose dependence is most pronounced for doses lower than 3 Gy (RBE). However, both the LEM predictions and experimental data show only a weak dependence of RBE on the tissue type, as characterized by the α/β ratio, which is considered insignificant with regard to the general uncertainties of RBE. The RBE predicted by the LEM shows overall very good agreement with the experimental data within the SOBP region and is in better agreement with the experimental data than the constant RBE of 1.1 that is currently applied in the clinics. All RBE trends deduced from the experiments were also reflected by the LEM predictions, which are purely based on input parameters derived from low-LET photon radiation.
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Affiliation(s)
- Rebecca Grün
- Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
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Facoetti A, Vischioni B, Ciocca M, Ferrarini M, Furusawa Y, Mairani A, Matsumoto Y, Mirandola A, Molinelli S, Uzawa A, Vilches FG, Orecchia R. In vivo radiobiological assessment of the new clinical carbon ion beams at CNAO. RADIATION PROTECTION DOSIMETRY 2015; 166:379-382. [PMID: 25877541 DOI: 10.1093/rpd/ncv145] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this article, the in vivo study performed to evaluate the uniformity of biological doses within an hypothetical target volume and calculate the values of relative biological effectiveness (RBE) at different depths in the spread-out Bragg peak (SOBP) of the new CNAO (National Centre for Oncological Hadrontherapy) carbon beams is presented, in the framework of a typical radiobiological beam calibration procedure. The RBE values (relative to (60)Co γ rays) of the CNAO active scanning carbon ion beams were determined using jejunal crypt regeneration in mice as biological system at the entrance, centre and distal end of a 6-cm SOBP. The RBE values calculated from the iso-effective doses to reduce crypt survival per circumference to 10, ranged from 1.52 at the middle of the SOBP to 1.75 at the distal position and are in agreement with those previously reported from other carbon ion facilities. In conclusion, this first set of in vivo experiments shows that the CNAO carbon beam is radiobiologically comparable with the NIRS (National Institute of Radiological Sciences, Chiba, Japan) and GSI (Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany) ones.
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Affiliation(s)
- A Facoetti
- CNAO Foundation, Via Campeggi 53, Pavia 27100, Italy
| | - B Vischioni
- CNAO Foundation, Via Campeggi 53, Pavia 27100, Italy
| | - M Ciocca
- CNAO Foundation, Via Campeggi 53, Pavia 27100, Italy
| | - M Ferrarini
- CNAO Foundation, Via Campeggi 53, Pavia 27100, Italy
| | - Y Furusawa
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inageku, Chiba, Japan
| | - A Mairani
- CNAO Foundation, Via Campeggi 53, Pavia 27100, Italy
| | - Y Matsumoto
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inageku, Chiba, Japan
| | - A Mirandola
- CNAO Foundation, Via Campeggi 53, Pavia 27100, Italy
| | - S Molinelli
- CNAO Foundation, Via Campeggi 53, Pavia 27100, Italy
| | - A Uzawa
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inageku, Chiba, Japan
| | | | - R Orecchia
- CNAO Foundation, Via Campeggi 53, Pavia 27100, Italy Department of Radiation Oncology, European Institute of Oncology, via Ripamonti 435, Milan, Italy University of Milan
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8
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Hirayama R, Uzawa A, Obara M, Takase N, Koda K, Ozaki M, Noguchi M, Matsumoto Y, Li H, Yamashita K, Koike S, Ando K, Shirai T, Matsufuji N, Furusawa Y. Determination of the relative biological effectiveness and oxygen enhancement ratio for micronuclei formation using high-LET radiation in solid tumor cells: An in vitro and in vivo study. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2015; 793:41-7. [PMID: 26520371 DOI: 10.1016/j.mrgentox.2015.08.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Accepted: 08/10/2015] [Indexed: 11/27/2022]
Abstract
We determined the relative biological effectiveness (RBE) and oxygen enhancement ratio (OER) of micronuclei (MN) formation in clamped (hypoxic) and non-clamped (normoxic) solid tumors in mice legs following exposure to X-rays and heavy ions. Single-cell suspensions (aerobic) of non-irradiated tumors were prepared in parallel and used directly to determine the radiation response for aerobic cells. Squamous cell carcinoma (SCCVII) cells were transplanted into the right hind legs of syngeneic C3H/He male mice. Irradiation doses with either X-rays or heavy ions at a dose-averaged LET (linear energy transfer) of 14-192keV/μm were delivered to 5-mm diameter tumors and aerobic single-cells in sample-tubes. After irradiation, the tumors were excised and trypsinized to observe MN in single-cells. The single-cell suspensions were used for MN formation assays. The RBE values increased with increasing LET. The maximum RBE values for the three different oxygen conditions; hypoxic tumor, normoxic tumor, and aerobic cells, were 8.18, 5.30, and 3.76 at an LET of 192keV/μm, respectively. After X-irradiation, the OERh/n values (hypoxic tumor/normoxic tumor) were lower than the OERh/a (hypoxic tumor/aerobic cells), and were 1.73 and 2.58, respectively. We found that the OER for the in vivo studies were smaller in comparison to that for the in vitro studies. Both of the OER values at 192keV/μm were small in comparison to those of the X-ray irradiated samples. The OERh/n and OERh/a values at 192keV/μm were 1.12 and 1.19, respectively. Our results suggest that high LET radiation has a large biological effect even if a solid tumor includes substantial numbers of hypoxic cells. To conclude, we found that the RBE values under each oxygen state for non-MN fraction increased with increasing LET and that the OER values for both tumors in vivo and cells in vitro decreased with increasing LET.
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Affiliation(s)
- Ryoichi Hirayama
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan.
| | - Akiko Uzawa
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Maki Obara
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Nobuhiro Takase
- School of Engineering, Tokai University, 1117 Kitakaname, Hiratsuka-shi, Kanagawa 259-1292, Japan
| | - Kana Koda
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Masakuni Ozaki
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Miho Noguchi
- Advanced Science Research Center, Japan Atomic Energy Agency (JAEA), 2-4 Shirakata-Shirane, Tokai-mura, Naka-gun, Ibaraki 319-1195, Japan
| | - Yoshitaka Matsumoto
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Huizi Li
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Kei Yamashita
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Sachiko Koike
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Koichi Ando
- Heavy Ion Medical Center, Gunma University, 3-39-22 Showa-machi, Maebashi-shi, Gunma 371-8511, Japan
| | - Toshiyuki Shirai
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Naruhiro Matsufuji
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Yoshiya Furusawa
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
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Paganetti H. Relative biological effectiveness (RBE) values for proton beam therapy. Variations as a function of biological endpoint, dose, and linear energy transfer. Phys Med Biol 2014; 59:R419-72. [PMID: 25361443 DOI: 10.1088/0031-9155/59/22/r419] [Citation(s) in RCA: 601] [Impact Index Per Article: 60.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Proton therapy treatments are based on a proton RBE (relative biological effectiveness) relative to high-energy photons of 1.1. The use of this generic, spatially invariant RBE within tumors and normal tissues disregards the evidence that proton RBE varies with linear energy transfer (LET), physiological and biological factors, and clinical endpoint. Based on the available experimental data from published literature, this review analyzes relationships of RBE with dose, biological endpoint and physical properties of proton beams. The review distinguishes between endpoints relevant for tumor control probability and those potentially relevant for normal tissue complication. Numerous endpoints and experiments on sub-cellular damage and repair effects are discussed. Despite the large amount of data, considerable uncertainties in proton RBE values remain. As an average RBE for cell survival in the center of a typical spread-out Bragg peak (SOBP), the data support a value of ~1.15 at 2 Gy/fraction. The proton RBE increases with increasing LETd and thus with depth in an SOBP from ~1.1 in the entrance region, to ~1.15 in the center, ~1.35 at the distal edge and ~1.7 in the distal fall-off (when averaged over all cell lines, which may not be clinically representative). For small modulation widths the values could be increased. Furthermore, there is a trend of an increase in RBE as (α/β)x decreases. In most cases the RBE also increases with decreasing dose, specifically for systems with low (α/β)x. Data on RBE for endpoints other than clonogenic cell survival are too diverse to allow general statements other than that the RBE is, on average, in line with a value of ~1.1. This review can serve as a source for defining input parameters for applying or refining biophysical models and to identify endpoints where additional radiobiological data are needed in order to reduce the uncertainties to clinically acceptable levels.
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Affiliation(s)
- Harald Paganetti
- Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, 30 Fruit Street, Boston, MA 02114, USA
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Evaluation of SCCVII tumor cell survival in clamped and non-clamped solid tumors exposed to carbon-ion beams in comparison to X-rays. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2013; 756:146-51. [DOI: 10.1016/j.mrgentox.2013.05.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 05/10/2013] [Indexed: 11/22/2022]
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Ogawa R, Morii A, Watanabe A, Cui ZG, Kagiya G, Fukuda S, Kume K, Hasegawa T, Hatashita M, Izumi H, Ishimoto T, Feril LB. Development of a therapeutically important radiation induced promoter. Bioengineered 2012; 4:44-9. [PMID: 22929999 DOI: 10.4161/bioe.21965] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Radio-genetic therapy is a combination of radiation therapy and gene therapy that may solve some of the problems associated with conventional radiotherapy. A promoter responsive to radiation was obtained from a promoter library composed of DNA fragments created by linking the TATA box signal to randomly combined binding sequences of transcription factors that are reactive to radiation. Each promoter connected to the luciferase gene, was evaluated by luciferase expression enhancement in transfected cells after X-ray irradiation. The reactivity of the best promoter was improved by the random introduction of point mutations and the resultant promoter showed more than a 20-fold enhancement of the luciferase expression after X-ray irradiation at 10 Gy. The expression of downstream genes was also enhanced in stably transfected cells not only by X-rays but also by proton beam irradiation; and either enhancement was attenuated when an anti-oxidant was added, thus suggesting the involvement of oxidative stress in the promoter activation. Constructed promoters were also activated in tumors grown in mice. In addition, cell killing with the fcy::fur gene (a suicide gene converting 5-fluorocytosin to highly toxic 5-fluorouracil) increased dose-dependently with 5-fluorocytosin only after X-ray irradiation in vitro. These results suggest that promoters obtained through this method could be used for possible clinical applications.
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Affiliation(s)
- Ryohei Ogawa
- Department of Radiological Sciences; Graduate School of Medicine and Pharmaceutical Sciences; University of Toyama; Toyama, Japan.
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12
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Gerelchuluun A, Hong Z, Sun L, Suzuki K, Terunuma T, Yasuoka K, Sakae T, Moritake T, Tsuboi K. Induction of in situ DNA double-strand breaks and apoptosis by 200 MeV protons and 10 MV X-rays in human tumour cell lines. Int J Radiat Biol 2010; 87:57-70. [PMID: 20954835 DOI: 10.3109/09553002.2010.518201] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To clarify the properties of clinical high-energy protons by comparing with clinical high-energy X-rays. MATERIALS AND METHODS Human tumor cell lines, ONS76 and MOLT4, were irradiated with 200 MeV protons or 10 MV X-rays. In situ DNA double-strand breaks (DDSB) induction was evaluated by immunocytochemical staining of phosphorylated histone H2AX (γ-H2AX). Apoptosis was measured by flow-cytometry after staining with Annexin V. The relative biological effectiveness (RBE) was obtained by clonogenic survival assay. RESULTS DDSB induction was significantly higher for protons than X-rays with average ratios of 1.28 (ONS76) and 1.59 (MOLT4) at 30 min after irradiation. However the differences became insignificant at 6 h. Also, apoptosis induction in MOLT4 cells was significantly higher for protons than X-rays with an average ratio of 2.13 at 12 h. However, the difference became insignificant at 20 h. RBE values of protons to X-rays at 10% survival were 1.06 ± 0.04 and 1.02 ± 0.15 for ONS76 and MOLT4, respectively. CONCLUSIONS Cell inactivation may differ according to different timings and/or endpoints. Proton beams demonstrated higher cell inactivation than X-rays in the early phases. These data may facilitate the understanding of the biological properties of clinical proton beams.
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Affiliation(s)
- Ariungerel Gerelchuluun
- Proton Medical Research Center, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
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Minohara S, Fukuda S, Kanematsu N, Takei Y, Furukawa T, Inaniwa T, Matsufuji N, Mori S, Noda K. Recent innovations in carbon-ion radiotherapy. JOURNAL OF RADIATION RESEARCH 2010; 51:385-392. [PMID: 20679740 DOI: 10.1269/jrr.10028] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
In the last few years, hospital-based facilities for carbon-ion radiotherapy are being constructed and proposed in Europe and Asia. During the next few years, several new facilities will be opened for carbon-ion radiotherapy in the world. These facilities in operation or under construction are categorized in two types by the beam shaping method used. One is the passive beam shaping method that is mainly improved and systematized for routine clinical use at HIMAC, Japan. The other method is active beam shaping which is also known as beam scanning adopted at GSI/HIT, Germany. In this paper an overview of some technical aspects for beam shaping is reported. The technique of passive beam shaping is established for stable clinical application and has clinical result of over 4000 patients in HIMAC. In contrast, clinical experience of active beam shaping is about 400 patients, and there is no clinical experience to respiratory moving target. A great advantage of the active beam shaping method is patient-specific collimator-less and compensator-less treatment. This may be an interesting potential for adaptive radiotherapy.
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Affiliation(s)
- Shinichi Minohara
- Department of Accelerator and Medical Physics, Research Center for Particle Therapy, National Institute of Radiological Sciences, Inage, Chiba, Japan.
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14
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Akino Y, Teshima T, Kihara A, Kodera-Suzumoto Y, Inaoka M, Higashiyama S, Furusawa Y, Matsuura N. Carbon-ion beam irradiation effectively suppresses migration and invasion of human non-small-cell lung cancer cells. Int J Radiat Oncol Biol Phys 2009; 75:475-81. [PMID: 19735871 DOI: 10.1016/j.ijrobp.2008.12.090] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2008] [Revised: 12/22/2008] [Accepted: 12/30/2008] [Indexed: 10/20/2022]
Abstract
PURPOSE Control of cancer metastasis is one of the most important issues in cancer treatment. We previously demonstrated that carbon particle irradiation suppresses the metastatic potential of cancer cells, and many studies have reported that photon irradiation promotes it. The purpose of this study was to investigate the effect of carbon beam on non-small-cell lung cancer (NSCLC) cell aggressiveness and gene expression. METHODS AND MATERIALS A549 (lung adenocarcinoma) and EBC-1 (lung squamous cell carcinoma) cells were treated with 290 MeV/nucleon carbon ion beam at the Heavy Ion Medical Accelerator in Chiba or with 4-MV X-ray at Osaka University. We tested proliferative, migratory, and invasive activities by cell proliferation assay, Boyden chamber assay, and Matrigel chemoinvasion assay, respectively. cDNA microarray and reverse transcription polymerase chain reaction were also performed to assess mRNA expression alteration. RESULTS X-irradiation increased cell proliferation of A549 cells at 0.5 Gy, whereas high-dose X-ray reduced migration and invasion of A549 cells. By contrast, carbon beam irradiation did not enhance proliferation, and it reduced the migration and invasion capabilities of both A549 and EBC-1 cells more effectively than did X-irradiation. Carbon beam irradiation induced alteration of various gene expression profiles differently from X-ray irradiation. mRNA expression of ANLN, a homologue of anillin, was suppressed to 60% levels of basal expression in carbon beam-irradiated A549 cells after 12 h. CONCLUSION Carbon beam effectively suppresses the metastatic potential of A549 and EBC-1 cells. Carbon beam also has different effects on gene expressions, and downregulation of ANLN was induced only by carbon beam irradiation.
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Affiliation(s)
- Yuichi Akino
- Department of Radiation Oncology, Osaka University Graduate School of Medicine and Health Science, Suita, Osaka, Japan
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15
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Uzawa A, Ando K, Koike S, Furusawa Y, Matsumoto Y, Takai N, Hirayama R, Watanabe M, Scholz M, Elsässer T, Peschke P. Comparison of biological effectiveness of carbon-ion beams in Japan and Germany. Int J Radiat Oncol Biol Phys 2009; 73:1545-51. [PMID: 19306751 DOI: 10.1016/j.ijrobp.2008.12.021] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2008] [Revised: 12/09/2008] [Accepted: 12/09/2008] [Indexed: 11/16/2022]
Abstract
PURPOSE To compare the biological effectiveness of 290 MeV/amu carbon-ion beams in Chiba, Japan and in Darmstadt, Germany, given that different methods for beam delivery are used for each. METHODS AND MATERIALS Murine small intestine and human salivary gland tumor (HSG) cells exponentially growing in vitro were irradiated with 6-cm width of spread-out Bragg peaks (SOBPs) adjusted to achieve nearly identical beam depth-dose profiles at the Heavy-Ion Medical Accelerator in Chiba, and the SchwerIonen Synchrotron in Darmstadt. Cell kill efficiencies of carbon ions were measured by colony formation for HSG cells and jejunum crypts survival in mice. Cobalt-60 gamma rays were used as the reference radiation. Isoeffective doses at given survivals were used for relative biological effectiveness (RBE) calculations and interinstitutional comparisons. RESULTS Isoeffective D(10) doses (mean +/- standard deviation) of HSG cells ranged from 2.37 +/- 0.14 Gy to 3.47 +/- 0.19 Gy for Chiba and from 2.31 +/- 0.11 Gy to 3.66 +/- 0.17 Gy for Darmstadt. Isoeffective D(10) doses of gut crypts after single doses ranged from 8.25 +/- 0.17 Gy to 10.32 +/- 0.14 Gy for Chiba and from 8.27 +/- 0.10 Gy to 10.27 +/- 0.27 Gy for Darmstadt, whereas isoeffective D(30) doses after three fractionated doses were 9.89 +/- 0.17 Gy through 13.70 +/- 0.54 Gy and 10.14 +/- 0.20 Gy through 13.30 +/- 0.41 Gy for Chiba and Darmstadt, respectively. Overall difference of RBE between the two facilities was 0-5% or 3-7% for gut crypt survival or HSG cell kill, respectively. CONCLUSION The carbon-ion beams at the National Institute of Radiological Sciences in Chiba, Japan and the Gesellschaft für Schwerionenforschung in Darmstadt, Germany are biologically identical after single and daily fractionated irradiation.
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Affiliation(s)
- Akiko Uzawa
- Heavy-Ion Radiobiology Research Group, Research Center of Charged Particle Therapy, National Institute of Radiological Sciences, Chiba, Japan
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