[1] Kyoto Katsura Hosp, Kyoto, Japan
[2] Kanagawa Canc Ctr, Dept Gastrointestinal Surg, Yokohama, Kanagawa, Japan
[3] Sano Hosp, Gastrointestinal Canc Ctr, Kobe, Hyogo, Japan
[4] Osaki Citizen Hosp, Dept Med Oncol, Osaki, Japan
[5] Shizuoka Canc Ctr Hosp, Div Colon & Rectal Surg, Shizuoka, Japan
[6] Japan Community Hlth Care Org, Kyushu Hosp, Dept Hematol Oncol, Kitakyushu, Fukuoka, Japan
[7] Fukui Ken Saiseikai Hosp, Fukui, Japan
[8] Jichi Med Univ, Saitama, Japan
[9] Hyogo Prefectural Nishinomiya Hosp, Nishinomiya, Hyogo, Japan
[10] Hamanomachi Hosp, Dept Surg, Fukuoka, Japan
[11] Natl Canc Ctr Hosp East, Kashiwa, Chiba, Japan
[12] Chigasaki Municipal Hosp, Dept Surg, Chigasaki, Kanagawa, Japan
[13] Japanese Red Cross Kochi Hosp, Dept Surg, Kochi, Japan
[14] Kyushu Univ, Fukuoka, Japan
[15] Shizuoka Canc Ctr, Div Gastrointestinal Oncol, Shizuoka, Japan
[16] Japanese Red Cross Med Ctr, Dept Surg Oncol, Tokyo, Japan
[17] Yokohama City Univ, Sch Med, Dept Biostat, Yokohama, Kanagawa, Japan
[18] Kyushu Cent Hosp, Fukuoka, Japan