[1] Fukui Prefectural Hosp, Dept Canc Therapy Ctr, Fukui 9108526, Japan
[2] Fukui Social Insurance Hosp, Dept Internal Med, Fukui, Japan
[3] Osaka Med Ctr Canc & Cardiovasc Dis, Dept Canc Control & Stat, Osaka, Japan
[4] Natl Canc Ctr, Canc Informat Serv, Tokyo 104, Japan
[5] Natl Canc Ctr, Surveillance Div, Ctr Canc Control, Tokyo 104, Japan
[6] Natl Canc Ctr, Informat Serv, Tokyo 104, Japan
[7] Jichi Med Univ, Dept Publ Hlth, Shimotsuke, Japan