[1] Natl Hosp Org Osaka Natl Hosp, Osaka, Japan
[2] Natl Hosp Org, Osaka Natl Hosp, Dept Surg, Osaka, Japan
[3] Natl Canc Ctr Hosp East, Dept Gastroenterol & Gastrointestinal Oncol, Kashiwa, Chiba, Japan
[4] Natl Canc Ctr Hosp East, Dept Colorectal Surg, Kashiwa, Chiba, Japan
[5] Natl Canc Ctr Hosp East, Clin Res Support Off, Kashiwa, Chiba, Japan
[6] Natl Canc Ctr Hosp East, Div Canc Immunol, Exploratory Oncol Res & Clin Trial Ctr, Kashiwa, Chiba, Japan
[7] Natl Canc Ctr Hosp East, Kashiwa, Chiba, Japan
[8] Hokkaido Univ Hosp, Dept Gastroenterol & Hepatol, Sapporo, Hokkaido, Japan
[9] Hokkaido Univ Hosp, Div Canc Ctr, Sapporo, Hokkaido, Japan
[10] Hokkaido Univ Hosp, Dept Gastroenterol Surg, Sapporo, Hokkaido, Japan
[11] Natl Canc Ctr Hosp East, Exploratory Oncol Res & Clin Trial Ctr, Div Pathol, Kashiwa, Chiba, Japan