[1] Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Dept Gastroenterol & Hepatol, Okayama 7008530, Japan
[2] Okayama Univ Hosp, Dept Endoscopy, Okayama, Japan
[3] Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Dept Hematol & Oncol, Okayama 7008530, Japan
[4] Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Dept Pathol, Okayama 7008530, Japan