[1] Natl Canc Ctr Hosp East, Dept Hepatobiliary & Pancreat Oncol, 6-5-1 Kashiwanoha, Kashiwa, Chiba 2778577, Japan
[2] Natl Canc Ctr, Japan Clin Oncol Grp Data Ctr, Operat Off, Tokyo, Japan
[3] Yamaguchi Univ, Grad Sch Med, Dept Gastroenterol Breast & Endocrine Surg, Ube, Japan
[4] Kansai Med Univ, Div Pancreatobiliary Surg, Dept Surg, Hirakata, Japan
[5] Kanagawa Canc Ctr, Dept Gastroenterol, Yokohama, Japan
[6] Kanazawa Univ Hosp, Dept Gastroenterol, Kanazawa, Japan
[7] Natl Canc Ctr, Hepatobiliary & Pancreat Oncol, Tokyo, Japan
[8] Kagoshima Univ, Grad Sch Med & Dent Sci, Digest & Lifestyle Dis, Kagoshima, Japan
[9] Kyoto Univ, Grad Sch Med, Div Hepatobiliary Pancreat Surg & Transplantat, Dept Surg, Kyoto, Japan
[10] Yokohama City Univ, Med Ctr, Gastroenterol Ctr, Yokohama, Japan
[11] Wakayama Med Univ, Dept Surg 2, Wakayama, Japan
[12] Nagasaki Univ, Grad Sch Biomed Sci, Dept Gastroenterol & Hepatol, Nagasaki, Japan
[13] Saitama Canc Ctr, Dept Gastroenterol, Saitama, Japan
[14] Tokyo Womens Med Univ, Dept Chemotherapy & Palliat Care, Tokyo, Japan
[15] NHO Osaka Natl Hosp, Dept Gastroenterol & Hepatol, Osaka, Japan
[16] Hyogo Canc Ctr, Dept Gastroenterol Oncol, Akashi, Japan
[17] Kyorin Univ, Fac Med, Dept Med Oncol, Tokyo, Japan
[18] Niigata Canc Ctr Hosp, Dept Internal Med, Niigata, Japan
[19] Tochigi Canc Ctr, Dept Med Oncol, Utsunomiya, Japan
[20] Sapporo Med Univ, Dept Gastroenterol & Hepatol, Sch Med, Sapporo, Japan
[21] Ishikawa Prefectural Cent Hosp, Dept Gastroenterol, Kanazawa, Japan
[22] Chiba Canc Ctr, Div Gastroenterol, Chiba, Japan
[23] St Marianna Univ, Sch Med, Dept Clin Oncol, Kawasaki, Japan
[24] Natl Hosp Org Shikoku Canc Ctr, Dept Gastrointestinal Med Oncol, Matsuyama, Japan