Ethics approval and consent to participate
This study was approved by the ethics committee of a senior facility (Ethics Committee of Toho University Omori Medical Center, reference number: 27-148). Informed consent was waived due to the study design.
Consent for publication
Not applicable.
Availability of data and materials
The dataset used this study are currently unavailable because it contains materials in unpublished manuscripts.
Competing interests
YN has received lecturer fees from Janssen Pharmaceutical K.K.
TY, MA, TS, KY, KY, HY, MO, YM, HO, KY, AN, KK, RO, AT and KJ declare no conflict of interest.
Funding
This study was supported by a Grant-in-aid for research on radiation oncology of JASTRO 2015-2016 which was provided by public corporation "Koueki Shadan Hojin Nihon Houshasenn Shuyou Gakkai" in Japanese.
Authors' contributions
Conception and design: YN and TY.
Provision of study patients: TY, YN, MA, TS, KY, KY, HY, MO, YM, HO, KY, AN, KK and RO.
Data analysis and interpretation: TY and KJ.
Manuscript draft: TY.
Manuscript editing and revision NY, MA, TS, KY, KY, HY, MO, YM, HO, KY, AN, KK, RO, AT and KJ.
Final approval of the manuscript: All authors.
Acknowledgements
We acknowledge the collaboration of many radiation oncologists in Japan. We thank Drs. Akira Anbai, Gencho Kuga, Hajime Ikeda, Hideya Yamazaki, Hidekazu Tanaka, Hisashi Kaizu, Hiroki Kobayashi, Hisao Kakuhara, Ichiro Ogino, Imi Takanashi, Junichi Yokouchi, Kana Kobayashi, Katsuyuki Shirai, Keisuke Fujimoto, Kenji Nagata, Kentaro Yamamoto, Koda Ryuichi, Kosuke Amano, Koutaro Terashima, Masaaki Yamashina, Masayoshi Yamada, Michiko Imai, Miyako Myojin, Nanae Yamaguchi, Nobuhiko Yoshikawa, Nobuhisa Mabuchi, Osamu Suzuki, Saeko Hirota, Satoshi Itasaka, Seiji Kubota, Shigetoshi Shimamoto, Shinichi Ogawa, Shinya Takemoto, Shizuko Ohashi, Syuji Otsu, Takanori Fukuda, Takashi Sakamoto, Takashi Kawanaka, Takuya Yamazaki, Tetsuo Nonaka, Tetsuo Saito, Tetsuya Inoue, Toshiki Kawamura, Toshinori Soejima, Tomoyasu Kumano, Toru Sakayauchi, Tsunehiko Kan, Yasuhiro Dekura, Yasuo Matsumoto, Yoshiaki Okamoto, Yoshisuke Matsuoka, Yo Ushijima, Yuko Shirata, Yumi Sato, Yu Takada and Yutaka Naoi.
Author details
1 Department of Radiation Oncology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan. 2 Department of Radiology, Toho University Omori Medical Center, 6-11-1 Omorinishi, Ota-ku, Tokyo 143-8540, Japan. 3 Department of Public Health, Kurume University School of Medicine, 67, Asahi-machi, Kurume 830-0011, Japan. 4 Department of Radiation Oncology, Hirosaki University, 1 Bunkyo-cho, Hirosaki 036-8560, Japan. 5 Department of Radiation Oncology and Image-Applied Therapy, Kyoto University Graduate School of Medicine, 54 Shogoinkawahara-cho, Sakyo-ku, Kyoto 606-8501, Japan. 6 Department of Radiation Oncology, Seirei Mikatahara General Hospital, 3453 Mikatahara-cho, Kita-ku, Hamamatsu 433-8558, Japan. 7 Department of Radiation Oncology, Fukuyama City Hospital, 5-23-1 Zao-cho, Fukuyama 721-8511, Japan. 8 Department of Radiology, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan. 9 Department of Radiation Oncology, Shizuoka City Shimizu Hospital, 1231 Miyakami, Shimizu-ku, Shizuoka 424-8636, Japan. 10 Department of Radiology, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601 Nagoya, Japan. 11 Department of Radiology, Yamanashi University, 1110 Shimokato, Chuo 409-3898, Japan. 12 Department of Radiology, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan. 13 Department of Radiation Oncology, Shikoku Cancer Center, 160 Minamiumemoto-machi, Matsuyama 791-0280, Japan. 14 Department of Proton Beam Therapy, Okayama University, 2-5-1 Shikata-cho, Kitaku, Okayama 700-8558, Japan. 15 Department of Radiology, Miyakojima IGRT Clinic, 1-16-22 Miyakojima-hondori, Miyakojima-ku, Osaka 534-0021, Japan.