[1] Kyoto Univ Hosp, Dept Clin Oncol, Kyoto, Japan
[2] Chiba Canc Ctr, Clin Trial Promot Dept, Chiba, Japan
[3] Tokyo Komagome Hosp, Bunkyo Ku, Tokyo, Japan
[4] Natl Canc Ctr, Ctr Res Adm & Support, JCOG Data Ctr Operat Off, Tokyo, Japan
[5] Natl Canc Ctr Hosp East, Kashiwa, Chiba, Japan
[6] Canc Inst Hosp, Dept Gastroenterol, Tokyo, Japan
[7] Shizuoka Canc Ctr, Div Endoscopy, Shizuoka, Japan
[8] Toranomon Gen Hosp, Tokyo, Japan
[9] Osaka Med Ctr Canc & Cardiovasc Dis, Dept Gastrointestinal Oncol, Osaka, Japan
[10] Natl Canc Ctr, Tokyo, Japan
[11] Kobe Univ, Sch Med, Kobe, Hyogo, Japan
[12] Aichi Canc Ctr Hosp, Dept Endoscopy, Nagoya, Aichi, Japan
[13] Komagome Hosp, Dept Endoscopy, Tokyo, Japan
[14] Kitasato Univ, Dept Gastroenterol, Sch Med, Kanagawa, Japan
[15] Shikoku Canc Ctr, Dept Gastroenterol, Mtatsuyama, Ehime, Japan
[16] Natl Canc Ctr, Japan Clin Oncol Grp Data Ctr, Tokyo, Japan
[17] Shizuoka Canc Ctr, Dept Endoscopy, Sunto, Japan