1. Department of Surgery Kyoto University Graduate School of Medicine Kyoto Japan
2. Department of Surgery Baba Memorial Hospital Sakai Japan
3. Department of Colorectal Surgery Tochigi Cancer Center Utsunomiya Japan
4. Department of Gastroenterological Surgery Ishikawa Prefectural Central Hospital Kanazawa Japan
5. Department of Gastroenterological and Pediatric Surgery Oita University Faculty of Medicine Yufu Japan
6. Department of Surgery NTT Medical Center Shinagawa‐ku Japan
7. Department of Coloproctological Surgery Juntendo University Faculty of Medicine Bunkyo‐ku Japan
8. Department of Surgical Oncology Dokkyo Medical University Graduate School of Medicine Shimotsuga‐gun Japan
9. Department of Gastroenterological Surgery Tokai University School of Medicine Shibuya City Japan
10. Japanese Red Cross Osaka Hospital Osaka Japan
11. Department of Lower Gastrointestinal Surgery Kitasato University School of Medicine Sagamihara Japan
12. Kitasato University Kitasato Institute Hospital Minato City Japan