[1] Yokohama City Univ, Sch Med, Dept Internal Med & Clin Immunol, Yokohama, Kanagawa 232, Japan
[2] Kanagawa Canc Ctr, Dept Oncol, Yokohama, Kanagawa 2410815, Japan
[3] Yokohama City Univ, Med Ctr, Dept Hematol, Yokohama, Kanagawa 232, Japan
[4] Fujisawa City Hosp, Dept Hematol Immunol, Fujisawa, Kanagawa, Japan
[5] Shizuoka Red Cross Hosp, Dept Hematol, Shizuoka, Japan
[6] Yokosuka City Hosp, Dept Hematol, Yokosuka, Kanagawa, Japan
[7] Yokohama Ekisaikai Hosp, Dept Internal Med, Yokohama, Kanagawa, Japan
[8] Yamato Municipal Hosp, Dept Hematol, Yamato, Japan