[1] Yokohama City Univ, Grad Sch Med, Dept Internal Med & Clin Immunol, Yokohama, Kanagawa 232, Japan
[2] Canc Inst Hosp, Dept Hematol & Med Oncol, Tokyo, Japan
[3] Tochigi Canc Ctr, Div Hematol, Utsunomiya, Tochigi, Japan
[4] Natl Hosp Org, Natl Tokyo Med Ctr, Dept Internal Med, Div Hematol, Tokyo, Japan
[5] Gunma Canc Ctr, Dept Hematol, Ota, Japan
[6] Kanagawa Canc Ctr, Dept Med Oncol, Yokohama, Kanagawa 2410815, Japan
[7] Fukuoka Univ, Sch Med, Dept Med, Div Med Oncol Hematol & Infect Dis, Fukuoka 81401, Japan
[8] Jichi Med Univ, Dept Med, Div Hematol, Shimotsuke, Japan