[1] Univ Tokyo, Grad Sch Med, Dept Gastroenterol, Tokyo, Japan
[2] GTK Pancreat Canc Study Grp, Tokyo, Japan
[3] Keio Univ, Sch Med, Dept Pathol, Minato City, Japan
[4] JFCR, Inst Canc, Div Pathol, Tokyo, Japan
[5] JFCR, Canc Inst Hosp, Dept Pathol, Tokyo, Japan
[6] JFCR, Canc Inst Hosp, Dept Hepatobiliary Pancreat Med, Tokyo, Japan
[7] Univ Tokyo, Grad Sch Med, Dept Pathol, Tokyo, Japan
[8] Keio Univ, Sch Med, Dept Surg, Minato City, Japan
[9] Keio Univ, Dept Pathol, Minato City, Japan
[10] Univ Tokyo, Dept Gastroenterol, Tokyo, Japan