[1] Univ Tokyo, Hepatobiliary Pancreat Surg Div, Dept Surg, Grad Sch Med, Tokyo 1130033, Japan
[2] Japanese Red Cross Med Ctr, Dept Hepatobiliary Pancreat Surg, Tokyo, Japan
[3] Musashino Red Cross Hosp, Dept Gastroenterol, Musashino, Tokyo, Japan
[4] Juntendo Univ, Shizuoka Hosp, Dept Gastroenterol, Shizuoka, Japan
[5] Kinki Univ, Sch Med, Dept Gastroenterol & Hepatol, Higashiosaka, Osaka 577, Japan
[6] Kobe Univ, Div Hepatobiliary Pancreat Surg, Grad Sch Med, Kobe, Hyogo, Japan
[7] Keio Univ, Sch Med, Dept Pathol, Tokyo 108, Japan
[8] Kurume Univ Hosp, Dept Clin Lab Med, Kurume, Fukuoka, Japan
[9] Kanazawa Univ, Grad Sch Med Sci, Dept Radiol, Kanazawa, Ishikawa 9201192, Japan
[10] Univ Tokyo, Sch Publ Hlth, Dept Biostat, Tokyo 1130033, Japan