[1] Shimane Univ, Fac Med, Dept Digest & Gen Surg, Izumo, Shimane 6938501, Japan
[2] Shimane Univ, Fac Med, Cent Pathol Lab, Izumo, Shimane 6938501, Japan
[3] Izumo Citizen Hosp, Dept Surg, Izumo, Shimane, Japan
[4] Naze Tokushukai Hosp, Kagoshima, Japan
[5] Columbia Univ, Med Ctr, Div Digest & Liver Dis, New York, NY USA