[1] Asahikawa Med Univ, Asahikawa, Hokkaido, Japan
[2] Sapporo Higashi Tokushukai Hosp, Ctr Clin & Biomed Res, Sapporo, Hokkaido, Japan
[3] Shonan Kamakura Gen Hosp, Dept Gen Thorac Surg, Kamakura, Kanagawa, Japan
[4] Shonan Kamakura Gen Hosp, Div Clin Oncol Res, Kamakura, Kanagawa, Japan