[1] Nagoya Univ, Dept Gastroenterol & Hepatol, Grad Sch Med, Showa Ku, 65 Tsuruma Cho, Nagoya, Aichi 4668550, Japan
[2] Nagoya Univ Hosp, Data Coordinating Ctr, Dept Adv Med, Showa Ku, 65 Tsuruma Cho, Nagoya, Aichi 4668550, Japan
[3] Nagoya Univ Hosp, Dept Endoscopy, Showa Ku, 65 Tsuruma Cho, Nagoya, Aichi 4668550, Japan