[1] Japanese Fdn Canc Res, Tokyo, Japan
[2] Natl Canc Ctr, Dept Hepatobiliary & Pancreat Oncol, Tokyo, Japan
[3] Natl Canc Ctr, Tokyo, Japan
[4] Natl Canc Ctr, Ctr Res Adm & Support, Tokyo, Japan
[5] Natl Canc Ctr, Japan Clin Oncol Grp, Data Ctr, Operat Off, Tokyo, Japan
[6] Kanagawa Canc Ctr, Hepatobiliary & Pancreat Med Oncol Div, Dept Gastroenterol, Yokohama, Kanagawa, Japan
[7] Natl Canc Ctr Hosp East, Chiba, Japan
[8] Yokohama City Univ, Med Ctr, Gastroenterol Ctr, Yokohama, Kanagawa, Japan
[9] Shizuoka Prefectural Gen Hosp, Canc Ctr, Shizuoka, Japan
[10] Saitama Canc Ctr, Dept Gastroenterol, Saitama, Japan
[11] Aichi Canc Ctr Hosp, Dept Gastroenterol, Nagoya, Aichi, Japan
[12] Kansai Med Univ, Osaka, Japan
[13] Teikyo Univ, Sch Med, Tokyo, Japan
[14] Kobe Univ, Grad Sch Med, Kobe, Hyogo, Japan
[15] Teine Keijinkai Hosp, Ctr Gastroenterol, Sapporo, Hokkaido, Japan
[16] Natl Hosp Org Osaka Natl Hosp, Dept Hepatobiliary Pancreat Surg, Osaka, Japan
[17] Jichi Med Univ, Shimotsuke, Tochigi, Japan
[18] Natl Hosp Org Shikoku Canc Ctr, Matsuyama, Ehime, Japan
[19] Chiba Canc Ctr, Clin Res Ctr, Chiba, Japan
[20] Kyorin Univ, Fac Med, Tokyo, Japan