1. Colorectal GroupClinical Study Group of Osaka University (CSGO) Osaka Japan
2. Department of SurgeryOsaka Rosai Hospital Sakai Japan
3. Department of SurgeryKansai Rosai Hospital Amagasaki Japan
4. Department of Gastroenterological SurgeryOsaka University Graduate School of Medicine Suita Japan
5. Department of SurgeryOsaka General Medical Center Osaka Japan
6. Department of SurgeryToyonaka Municipal Hospital Toyonaka Japan
7. Department of SurgeryMinoh City Hospital Minoh Japan
8. Department of SurgerySakai City Medical Center Sakai Japan
9. Department of Gastroenterological SurgeryOsaka International Cancer Institute Osaka Japan
10. Department of SurgeryIkeda City Hospital Ikeda Japan
11. Department of Gastroenterological SurgeryHigashiosaka City Medical Center Higashiosaka Japan
12. Department of Therapeutics for Inflammatory Bowel DiseasesGraduate School of MedicineOsaka University Suita Japan
13. Division of Health SciencesGraduate School of MedicineOsaka University Suita Japan
14. Department of SurgeryNational Hospital Organization Osaka National Hospital Osaka Japan
15. Department of SurgeryNishinomiya Municipal Central Hospital Nishinomiya Japan
16. Department of Surgery and ScienceGraduate School of Medical SciencesKyushu University Fukuoka Japan