[1] Natl Canc Ctr Hosp East, Gastrointestinal Oncol Div, Kashiwa, Chiba, Japan
[2] Natl Canc Ctr Hosp East, Dept Gastroenterol & Gastrointestinal Oncol, Kashiwa, Chiba, Japan
[3] Natl Hosp Org Osaka Natl Hosp, Dept Surg, Osaka, Japan
[4] Kansai Rosai Hosp, Dept Surg, Amagasaki, Hyogo, Japan
[5] Osaki Citizen Hosp, Dept Med Oncol, Osaki, Japan
[6] Shizuoka Canc Ctr, Div Gastrointestinal Oncol, Shizuoka, Japan
[7] Hokkaido Univ Hosp, Ctr Canc, Sapporo, Hokkaido, Japan
[8] Kobe City Med Ctr Gen Hosp, Dept Med Oncol, Kobe, Hyogo, Japan
[9] Osaka Med Coll Hosp, Ctr Canc Chemotherapy, Takatsuki, Osaka, Japan
[10] Okayama Rosai Hosp, Med Oncol, Okayama, Japan
[11] Kyushu Univ, Dept Surg & Sci, Fukuoka, Japan
[12] Sano Hosp, Gastrointestinal Canc Ctr, Kobe, Hyogo, Japan
[13] Japan Community Hlth Care Org Kyushu Hosp, Dept Hematol Oncol, Kitakyushu, Fukuoka, Japan
[14] Chiba Canc Ctr, Gastroenterol, Chiba, Japan
[15] Takeda Pharmaceut Co Ltd, Med Affairs Dept, Tokyo, Japan
[16] Univ Tokyo, Dept Biostat, Sch Publ Hlth, Tokyo, Japan
[17] Japanese Fdn Canc Res, Canc Inst Hosp, Dept Gastroenterol Chemotherapy, Tokyo, Japan