[1] Natl Canc Ctr Hosp East, Dept Gastroenterol & Gastrointestinal Oncol, Chiba, Japan
[2] Natl Canc Ctr Hosp East, Dept Gastrointestinal Oncol, Kashiwa, Chiba, Japan
[3] Natl Canc Ctr Hosp East, Kashiwa, Chiba, Japan
[4] Natl Canc Ctr, Exploratory Oncol Res & Clin Trial Ctr, Kashiwa, Chiba, Japan
[5] Natl Canc Ctr Hosp East, Dept Gastroenterol & Gastrointestinal Oncol, Kashiwa, Chiba, Japan
[6] Natl Canc Ctr Hosp East, Chiba, Japan