[1] Nagasaki Univ, Dept Surg, Grad Sch Biomed Sci, Nagasaki 8528501, Japan
[2] Tokyo Med & Dent Univ, Grad Sch Med, Dept Hepatobiliary Pancreat Surg, Yamanashi, Japan
[3] Yamanashi Prefectural Cent Hosp, Dept Gastroenterol, Yamanashi, Japan
[4] Kinki Univ, Sch Med, Dept Internal Med, Div Gastroenterol & Hepatol, Tokyo, Japan
[5] Keio Univ, Dept Pathol, Tokyo, Japan
[6] Natl Canc Ctr, Dept Diagnost Radiol, Tokyo, Japan
[7] Japanese Red Cross Med Ctr, Dept Surg, Tokyo, Japan
[8] Univ Tokyo, Dept Biostat, Sch Hlth Sci & Nursing, Tokyo, Japan
[9] Osaka Univ, Grad Sch Med, Dept Surg, Osaka, Japan