[1] Okayama Univ, Dept Gastroenterol & Hepatol, Grad Sch Med Dent & Pharmaceut Sci, Okayama, Japan
[2] Okayama Univ, Dept Pathol, Grad Sch Med Dent & Pharmaceut Sci, Okayama, Japan
[3] Okayama Univ, Dept Hematol & Oncol, Grad Sch Med Dent & Pharmaceut Sci, Okayama, Japan
[4] Okayama Univ Hosp, Dept Pract Gastrointestinal Endoscopy, Okayama 7008558, Japan