[1] Univ Tokyo, Grad Sch Med, Dept Surg, Hepatobiliary Pancreat Surg Div, Tokyo 1138654, Japan
[2] Saitama Canc Ctr, Div Gastroenterol Surg, Saitama, Japan
[3] Univ Tokyo, Sch Publ Hlth, Dept Biostat, Tokyo 1138654, Japan
[4] Nihon Univ, Sch Med, Dept Digest Surg, Tokyo 102, Japan
[5] Musashino Red Cross Hosp, Dept Gastroenterol, Musashino, Tokyo, Japan
[6] Shinshu Univ, Sch Med, Dept Radiol, Matsumoto, Nagano, Japan
[7] Kinki Univ, Sch Med, Dept Gastroenterol & Hepatol, Higashiosaka, Osaka 577, Japan
[8] Kobe Univ, Grad Sch Med, Dept Surg, Div HepatobiliaryPancreat Surg, Kobe, Hyogo, Japan
[9] Keio Univ, Dept Pathol, Sch Med, Tokyo 108, Japan
[10] Kurume Univ Hosp, Dept Clin Lab Med, Kurume, Fukuoka, Japan
[11] Kanazawa Univ Hosp, Dept Gastroenterol, Kanazawa, Ishikawa, Japan