[1] Japanese Fdn Canc Res, Koto Ku, Tokyo, Japan
[2] Japanese Fdn Canc Res, Canc Inst Hosp, Dept Gastroenterol, Tokyo, Japan
[3] Japanese Fdn Canc Res, Canc Inst Hosp, Dept Gastrointestinal Oncol, Tokyo, Japan
[4] Japanese Fdn Canc Res, Canc Inst Hosp, Div Hepatobiliary & Pancreat Surg, Tokyo, Japan
[5] Japanese Fdn Canc Res, Canc Inst Hosp, Tokyo, Japan
[6] Keio Univ, Sch Med, Div Gastroenterol & Hepatol, Tokyo, Japan
[7] JFCR, Canc Inst Hosp, Tokyo, Japan