1. Division of Gastroenterological and General Surgery St. Marianna University School of Medicine Kawasaki Japan
2. Department of Surgery Teikyo University School of Medicine Tokyo Japan
3. Department of Surgery Tokyo Women's Medical University Yachiyo Medical Center Chiba Japan
4. Department of Digestive Surgery Nihon University School of Medicine Tokyo Japan
5. Department of Gastroenterological Surgery Tokyo Medical University Ibaraki Medical Center Ibaraki Japan
6. Department of Surgery Toho University Ohashi Medical Center Tokyo Japan
7. Department of Surgery, Institute of Gastroenterology Tokyo Women's Medical University Tokyo Japan
8. Department of Surgery Tohoku University Graduate School of Medicine Sendai Japan
9. Department of Hepato‐Biliary‐Pancreatic Surgery Tokyo Medical and Dental University Tokyo Japan
10. Department of Gastroenterological, Breast and Endocrine Surgery Yamaguchi University Graduate School of Medicine Yamaguchi Japan
11. National Center for Global Health and Medicine Tokyo Japan
12. Department of Gastroenterological Surgery II Hokkaido University Faculty of Medicine Sapporo Japan
13. Department of Surgery and Oncology, Graduate School of Medical Sciences Kyushu University Fukuoka Japan
14. Division of Hepatobiliary and Pancreatic Surgery, Department of General Surgery, Graduate School of Medicine Gunma University Maebashi Japan
15. Department of Gastroenterological Surgery Kagawa University Takamatsu Japan
16. Department of Hepato‐Biliary‐Pancreatic and Gastrointestinal Surgery, School of Medicine International University of Health & Welfare Chiba Japan
17. Department of Hepato‐Pancreatic‐Biliary and Breast Surgery Ehime University Graduate School of Medicine Toon Japan
18. Department of Surgery Tokai University School of Medicine Isehara Japan
19. Department of Gastroenterological Surgery Fujita Health University Bantane Hospital Nagoya Japan
20. Department of Gastroenterological and Transplant Surgery, Graduate School of Biomedical and Health Sciences Hiroshima University Hiroshima Japan
21. Department of Surgery Nagasaki University Graduate School of Biomedical Sciences Nagasaki Japan
22. Department of General Surgery, Graduate School of Medicine Chiba University Chiba Japan
23. Department of Surgery Nara Medical University Kashihara Japan
24. Department of Surgery, Saitama Medical Center Jichi Medical University Saitama Japan
25. Department of Surgery, Graduate School of Medicine Kyoto University Kyoto Japan
26. Department of Gastroenterological Surgery I Hokkaido University Graduate School of Medicine Sapporo Japan
27. Department of Surgery and Science, Faculty of Medicine, Academic Assembly University of Toyama Toyama Japan
28. Second Department of Surgery, School of Medicine Wakayama Medical University Wakayama Japan
29. Digestive Diseases Center International University of Health and Welfare Narita Hospital Narita Japan
30. Department of Gastroenterological Surgery Utsunomiya Memorial Hospital Utsunomiya Japan
31. Department of Gastroenterological Surgery Yokohama City University Graduate School of Medicine Yokohama Japan