1. Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka
2. Japan Clinical Oncology Group Data Center/Operations Office, National Cancer Center Hospital, Tokyo
3. Department of Surgery and Science, Faculty of Medicine, Academic Assembly, University of Toyama, Toyama
4. Second Department of Surgery, Wakayama Medical University, Wakayama
5. Department of Surgery, Teine Keijinkai Hospital, Hokkaido
6. Department of Surgery, Kindai University Faculty of Medicine, Osakasayama
7. Department of Digestive Surgery, Kagoshima University, Kagoshima
8. Department of Hepatobiliary and Pancreatic Surgery, National Cancer Center Hospital, Tokyo
9. Department of Gastroenterological Surgery, Graduate School of Medicine, Osaka University, Suita
10. Department of Gastroenterological, Breast and Endocrine Surgery, Yamaguchi University Graduate School of Medicine, Yamaguchi
11. Department of Surgery, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki
12. Department of Surgery, Tohoku University Graduate School of Medicine, Sendai
13. Department of Gastroenterological Surgery, Saitama Cancer Center, Saitama
14. Department of Hepato-Biliary-Pancreatic Surgery and Transplantation, Kanazawa University, Ishikawa
15. Department of Gastroenterological Surgery, Osaka International Cancer Institute, Osaka
16. Department of HepatoBiliary-Pancreatic Surgery, Tochigi Cancer Center, Tochigi
17. Department of Gastrointestinal Surgery, Kanagawa Cancer Center, Kanagawa
18. Division of Hepato-Biliary-Pancreatic Surgery, Department of Gastroenterological Surgery, Hyogo Medical University, Hyogo
19. Department of Hepatobiliary and Pancreatic Surgery, National Cancer Center Hospital East, Chiba
20. Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto
21. Department of Gastroenterology, Kanagawa Cancer Center, Kanagawa