[1] Univ Tokyo, Grad Sch Med, Dept Gastroenterol, Tokyo, Japan
[2] Univ Tokyo, Grad Sch Med, Dept Endoscopy & Endoscop Surg, Tokyo, Japan
[3] Tokyo Med Univ, Canc Inst Hosp JFCR, Dept Gastroenterol, Hachioji Med Ctr, Tokyo, Japan
[4] Tokyo Med Univ, Dept Gastroenterol & Hepatol, Hachioji Med Ctr, Tokyo, Japan
[5] Showa Univ, Sch Med, Dept Med, Div Gastroenterol, Tokyo, Japan
[6] Tokyo Med Univ Hosp, Dept Gastroenterol, Tokyo, Japan
[7] Nihon Univ, Dept Gastroenterol, Itabashi Hosp, Tokyo, Japan
[8] Toho Univ, Div Gastroenterol & Hepatol, Dept Internal Med, Ohashi Med Ctr, Tokyo, Japan
[9] Juntendo Univ, Grad Sch Med, Dept Gastroenterol, Tokyo, Japan
[10] Yokohama City Univ, Gastroentel Ctr, Med Ctr, Yokohama, Kanagawa, Japan
[11] Kitasato Univ Hosp, Dept Gastroenterol, Sagamihara, Kanagawa, Japan
[12] Saitama Med Univ, Dept Gastroenterol & Hepatol, Saitama Med Ctr, Saitama, Japan
[13] Saitama Med Univ, Dept Gastroenterol, Int Med Ctr, Saitama, Japan
[14] Asahi Gen Hosp, Dept Gastroenterol, Chiba, Japan
[15] Jichi Med Univ Hosp, Dept Gastroenterol, Shimotsuke, Tochigi, Japan
[16] Teikyo Univ Hosp, Dept Gastroenterol, Kawasaki, Kanagawa, Japan