1. Division of Gastroenterological Surgery; Department of Surgery; Tohoku University Graduate School of Medicine; 1-1 Seiryo-machi Aoba-ku Sendai 980-8574 Japan
2. Department of Surgery; Osaka Medical Center for Cancer and Cardiovascular Diseases; Osaka Japan
3. Department of Surgery; School of Medicine; Teikyo University; Tokyo Japan
4. Department of Surgery; Nara Medical University; Nara Japan
5. Department of Gastroenterological Surgery; Osaka University Graduate School of Medicine; Osaka Japan
6. Division of Hepato-Biliary-Pancreatic Surgery; Department of Surgery; Kobe University Graduate School of Medicine; Kobe Japan
7. Department of Surgery; Kansai Medical University; Osaka Japan
8. Department of Surgery; Institute of Biomedical and Health Sciences, Hiroshima University; Hiroshima Japan
9. Department of Hepatobiliary Pancreatic and Transplant Surgery; Mie University Graduate School of Medicine; Mie Japan
10. Department of Hepato-Biliary-Pancreatic Surgery; Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital; Tokyo Japan
11. Department of Surgery; Kurume University School of Medicine; Fukuoka Japan
12. Department of Gastroenterological Surgery; Graduate School of Medical Sciences; Kumamoto University; Kumamoto Japan
13. Department of Surgery; Tochigi Cancer Center; Utsunomiya Japan
14. Department of Surgery; Keio University School of Medicine; Tokyo Japan
15. Department of Gastroenterologic Surgery; Division of Cancer Medicine; Graduate School of Medicine Science; Kanazawa University; Kanazawa Japan
16. School of Health Sciences; Kagoshima University Faculty of Medicine; Kagoshima Japan
17. Department of Surgery; Saiseikai Kumamoto Hospital; Kumamoto Japan
18. Hepatobiliary and Pancreatic Surgery Division; National Cancer Center Hospital; Tokyo Japan
19. Second Department of Surgery; Wakayama Medical University; Wakayama Japan
20. Japanese Society of Hepato-Biliary-Pancreatic Surgery; Tokyo Japan