1. Department of Radiation Oncology and Image‐Applied Therapy, Graduate School of Medicine Kyoto University Kyoto Japan
2. QST Hospital, National Institutes for Quantum Science and Technology Chiba Japan
3. Department of Urology Aichi Cancer Center Nagoya Japan
4. Department of Pediatric Radiation Therapy Center/Pediatric Proton Beam Therapy Center Hebei Yizhou Cancer Hospital Zhuozhou City China
5. Department of Urology Wakayama Medical University Wakayama Japan
6. Biostatistics and Data Management Sapporo Medical University Sapporo Japan