[1] University of Tokyo,Department of Health Economics and Epidemiology Research, School of Public Health
[2] Toho University School of Medicine,Department of Gastroenterological Surgery (Omori)
[3] National Cancer Center Hospital East,Colorectal and Pelvic Surgery
[4] Gunma Prefectural Cancer Center,Department of Surgery
[5] Kurume University Faculty of Medicine,Department of Surgery
[6] Takano Hospital,Department of Surgery, Coloproctology Center
[7] Tokyo Medical and Dental University,Department of Surgical Oncology
[8] Teikyo University School of Medicine,Department of Surgery
[9] Yokohama Municipal Hospital,Department of Surgery
[10] Kameda General Hospital,Department of General Surgery
[11] Saitama Medical University International Medical Center,Department of Gastroenterological Surgery