[1] Saitama Canc Ctr, Saitama, Japan
[2] Kinki Univ, Sch Med, Osaka 589, Japan
[3] Teikyo Univ, Sch Med, Dept Surg, Tokyo 173, Japan
[4] Tokyo Med & Dent Univ, Grad Sch, Dept Surg Oncol, Tokyo, Japan
[5] Bristol Myers KK, Tokyo, Japan
[6] Merck Serono, Tokyo, Japan
[7] Misawa Municipal Hosp, Misawa, Japan