[1] Hiroshima City Hiroshima Citizens Hosp, Dept Internal Med, Naka Ku, 7-33 Moto Machi, Hiroshima 7308518, Japan
[2] Hiroshima City Hiroshima Citizens Hosp, Dept Surg, Naka Ku, 7-33 Moto Machi, Hiroshima 7308518, Japan
[3] Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Dept Gastroenterol & Hepatol, Kita Ku, 2-5-1 Shikata Cho, Okayama 7008558, Japan
[4] Hiroshima City Hiroshima Citizens Hosp, Dept Endoscopy, Naka Ku, 7-33 Moto Machi, Hiroshima 7308518, Japan