[1] Tokyo Womens Med Univ, Dept Surg, Yachiyo Med Ctr, 477-96,Owadashinden, Chiba 2768524, Japan
[2] Tokyo Womens Med Univ, Dept Chemotherapy & Palliat Care, Shinjuku ku, 8-1,Kawadacho,, Tokyo, Japan
[3] Tsukuba Gastroint Hosp, 1-2-39,Takamihara, Tsukuba, Ibaraki, Japan
[4] Toshima Met Hosp, Dept Surg, Itabashi ku, Sakaecho, Tokyo, Japan
[5] Tokyo Womens Med Univ, Dept Surg 2, Shinjuku ku, 8-1,Kawadacho, Tokyo, Japan
[6] Tokyo Womens Med Univ, Med Ctr East, Dept Surg, Arakawa ku, 2-1-10,Nishioku, Tokyo, Japan