[1] Ichikawa Gen Hosp, Tokyo Dent Coll, Dept Surg, Ichikawa, Japan
[2] Natl Canc Ctr Hosp Tokyo, Esophageal Surg Div, Tokyo, Japan
[3] Aichi Canc Ctr Hosp, Dept Thorac Surg, Nagoya, Aichi 464, Japan
[4] Keio Univ, Sch Med, Dept Surg, Tokyo 160, Japan
[5] Tochigi Canc Ctr, Dept Surg, Utsunomiya, Tochigi, Japan
[6] Tokyo Womens Med Univ, Inst Gastroenterol, Tokyo, Japan
[7] Niigata Canc Ctr Hosp, Dept Surg, Niigata, Japan
[8] Kanagawa Canc Ctr, Dept Surg, Yokohama, Kanagawa 2410815, Japan
[9] Shikoku Canc Ctr, Dept Surg, Matsuyama, Ehime, Japan
[10] Iwate Med Univ, Sch Med, Dept Surg, Morioka, Iwate 020, Japan
[11] Niigata Univ Med & Dent Hosp, Dept Surg, Niigata, Japan
[12] Osaka Natl Hosp, Natl Hosp Org, Dept Surg, Osaka, Japan
[13] Japan Clin Oncol Grp Data Ctr, Tokyo, Japan