1. Department of Gastroenterological Surgery; Gastroenterological Center; Cancer Institute Hospital of the Japanese Foundation for Cancer Research; Tokyo Japan
2. Study Group for Familial Adenomatous Polyposis in the Japanese Society for Cancer of the Colon and Rectum; Tokyo Japan
3. Department of Digestive Tract and General Surgery; Saitama Medical Center; Saitama Medical University; Saitama Japan
4. Department of Surgery; National Defense Medical College; Saitama Japan
5. Department of Gastrointestinal Surgery; Tokyo Medical and Dental University; Tokyo Japan
6. Department of Gastroenterological and Transplant Surgery; Hiroshima University; Hiroshima Japan
7. Department of Gastrointestinal and Pediatric Surgery; Mie University Graduate School of Medicine; Mie Japan
8. Digestive Disease Center; Northern Yokohama Hospital; Showa University; Yokohama Japan
9. Colorectal Surgery Division; National Cancer Center Hospital; Tokyo Japan
10. Department of Surgery; Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital; Tokyo Japan
11. Division of Lower GI Surgery; Department of Surgery; Hyogo College of Medicine; Hyogo Japan
12. Department of Surgical Oncology; Graduate School of Medicine; The University of Tokyo; Tokyo Japan
13. Tokyo Medical and Dental University; Tokyo Japan