[1] Southern Tohoku Gen Hosp, Dept Surg, Koriyama, Japan
[2] Fukushima Med Univ, Dept Minimally Invas Surg & Med Oncol, 1 Hikarigaoka, Fukushima, Fukushima 9601295, Japan
[3] Japanese Fdn Canc Res, Canc Inst Hosp, Dept Gastroenterol Surg, Tokyo, Japan
[4] Natl Canc Ctr Hosp East, Dept Gastr Surg, Kashiwa, Japan
[5] Keio Univ, Sch Med, Dept Surg, Tokyo, Japan
[6] Niigata Canc Ctr Hosp, Dept Digest Surg, Niigata, Japan