[1] Tokai Univ, Dept Gastroenterol, Sch Med, Isehara, Kanagawa, Japan
[2] Tokai Univ, Dept Gastroenterol, Sch Med, Hachioji Hosp, Tokyo, Japan
[3] Keio Univ, Ctr Prevent Med, Sch Med, Tokyo, Japan
[4] Tokai Univ, Dept Pathol, Hachioji Hosp, Sch Med, Tokyo, Japan