[1] Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Dept Gastroenterol & Hepatol, Okayama 7008558, Japan
[2] Kagawa Prefectural Cent Hosp, Dept Gastroenterol, Takamatsu, Kagawa 7608557, Japan
[3] Sumitomo Besshi Hosp, Dept Gastroenterol, Niihama 7928543, Japan
[4] Fukuyama City Hosp, Dept Internal Med, Fukuyama, Hiroshima 7218511, Japan
[5] Fukuyama Med Ctr, Dept Gastroenterol, Fukuyama, Hiroshima 7208520, Japan
[6] Hiroshima City Hiroshima Citizens Hosp, Dept Internal Med, Hiroshima 7308518, Japan
[7] Shikoku Canc Ctr, Dept Endoscopy, Matsuyama, Ehime 7910280, Japan
[8] Kurashiki Cent Hosp, Dept Gastroenterol & Hepatol, Kurashiki, Okayama 7108602, Japan
[9] Okayama Saiseikai Gen Hosp, Dept Internal Med, Okayama 7008511, Japan
[10] Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Dept Pathol, Okayama 700, Japan