Teiji Nishio1, Hidenobu Tachibana2, Yuki Kase3, Kenji Hotta2, Mitsuhiro Nakamura4, Masaya Tamura5, Toshiyuki Terunuma6, Toshiyuki Toshito7, Haruo Yamashita3, Satoshi Ishikura8, Hiroshi Fuji9, Tetsuo Akimoto2, Yasumasa Nishimura10. 1. Department of Medical Physics, Graduate School of Medicine, Tokyo Women's Medical University, Japan. Electronic address: nishio.teiji@twmu.ac.jp. 2. Division of Radiation Oncology and Particle Therapy, Exploratory Oncology Research and Clinical Trial Center, National Cancer Center, Kashiwa, Japan. 3. Proton Therapy Division, Shizuoka Cancer Center Research Institute, Japan. 4. Division of Medical Physics, Department of Information Technology and Medical Engineering, Human Health Sciences, Graduate School of Medicine, Kyoto University, Japan. 5. Department of Medical Physics, Hokkaido University Hospital, Sapporo, Japan. 6. Faculty of Medicine, University of Tsukuba, Japan. 7. Department of Proton Therapy Physics, Nagoya Proton Therapy Center, Nagoya City West Medical Center, Japan. 8. Department of Radiology, Graduate School of Medical Sciences, Nagoya City University, Japan. 9. Department of Radiation Oncology, National Center for Child Health and Development, Tokyo, Japan. 10. Department of Radiation Oncology, Kindai University Faculty of Medicine, Osaka-Sayama, Japan.
Abstract
BACKGROUND AND PURPOSE: In Japan, the first domestic clinical trial of proton beam therapy for the liver was initiated as the Japan Clinical Oncology Group trial (JCOG1315C: Non-randomized controlled study comparing proton beam therapy and hepatectomy for resectable hepatocellular carcinoma). Purposes of this study were to develop a new dosimetric verification system and to carry out a credentialing for the JCOG1315C clinical trial. MATERIALS AND METHODS: Accuracy and differences in doses in proton treatment planning among participating institutions were surveyed and investigated. We designed and developed a suitable water tank-type liver phantom for a dosimetric verification of proton beam therapy for liver. In a visiting survey of five institutions participating in the clinical trial, we performed the dosimetric verification using the liver phantom and an air-filled ionization chamber. RESULTS: The shape of the dose distributions calculated in proton treatment planning was characteristic and dependent on the manufacturers of the proton beam therapy system, the proton treatment planning system and the setup at the participating institutions. Widths of the lateral penumbra were 5.8-12.7 mm among participating institutions. The accuracy between the calculated and the measured doses in the proton irradiation was within 3% at five measurement points including both points on the isocenter and off the isocenter. CONCLUSIONS: These findings confirmed the accuracy of the delivery doses in the institutions participating in the clinical trial, and the clinical trial with integration of all institutions (five institutions) could be initiated.
BACKGROUND AND PURPOSE: In Japan, the first domestic clinical trial of proton beam therapy for the liver was initiated as the Japan Clinical Oncology Group trial (JCOG1315C: Non-randomized controlled study comparing proton beam therapy and hepatectomy for resectable hepatocellular carcinoma). Purposes of this study were to develop a new dosimetric verification system and to carry out a credentialing for the JCOG1315C clinical trial. MATERIALS AND METHODS: Accuracy and differences in doses in proton treatment planning among participating institutions were surveyed and investigated. We designed and developed a suitable water tank-type liver phantom for a dosimetric verification of proton beam therapy for liver. In a visiting survey of five institutions participating in the clinical trial, we performed the dosimetric verification using the liver phantom and an air-filled ionization chamber. RESULTS: The shape of the dose distributions calculated in proton treatment planning was characteristic and dependent on the manufacturers of the proton beam therapy system, the proton treatment planning system and the setup at the participating institutions. Widths of the lateral penumbra were 5.8-12.7 mm among participating institutions. The accuracy between the calculated and the measured doses in the proton irradiation was within 3% at five measurement points including both points on the isocenter and off the isocenter. CONCLUSIONS: These findings confirmed the accuracy of the delivery doses in the institutions participating in the clinical trial, and the clinical trial with integration of all institutions (five institutions) could be initiated.
Authors: Paige A Taylor; Jessica Lowenstein; David Followill; Stephen F Kry Journal: Int J Radiat Oncol Biol Phys Date: 2021-11-13 Impact factor: 7.038