1. Second Department of Surgery, School of Medicine; Wakayama Medical University; Wakayama Japan
2. Department of Surgical Oncology; Hokkaido University Graduate School of Medicine; N15 W7 Kita-ku, Sapporo Hokkaido 060-8638 Japan
3. Department of Surgery; Teikyo University School of Medicine; Tokyo Japan
4. Division of Hepato-Biliary-Pancreatic Surgery, Department of Surgery; Tohoku University Graduate School of Medicine; Sendai Japan
5. Department of Surgery; Kansai Medical University; Moriguchi Osaka Japan
6. Department of Surgery, Institute of Gastroenterology; Tokyo Women's Medical University; Tokyo Japan
7. Division of Clinical Medical Science, Department of Surgery; Hiroshima University Graduate School of Biomedical Sciences; Hiroshima Japan
8. Department of Hepato-Biliary-Pancreatic Surgery and Transplantation; Kyoto University; Kyoto Japan
9. Department of Biliary Pancreatic Surgery; Fujita Health University School of Medicine; Toyoake Aichi Japan
10. Department of Surgical Oncology; Kagoshima University; Kagoshima Kagoshima Japan
11. Department of Gastroenterological Surgery, Graduate School of Medical Science; Kanazawa University; Kanazawa Ishikawa Japan
12. Japanese Society of Hepato-Biliary-Pancreatic Surgery, Department of Surgery; Teikyo University School of Medicine; Tokyo Japan