Impact of Five Prophylactic Filgrastim Schedules on Hematologic Toxicity in Early Breast Cancer Patients Treated With Epirubicin and Cyclophosphamide

Purpose To evaluate the comparative efficacy of varying intensity schedules of recombinant human granulocyte colony-stimulating factor (G-CSF; filgrastim) support in preventing febrile neutropenia in early breast cancer patients treated with relatively high-dose epirubicin plus cyclophosphamide (EC). Patients and Methods From October 1991 to April 1994, 506 stage I and II breast cancer patients were randomly assigned to receive, in a factorial 2 × 2 design, epirubicin 120 mg/m2 and cyclophosphamide 600 mg/m2 intravenously on day 1 every 21 days for 4 cycles ± lonidamine ± G-CSF. The following five consecutive G-CSF schedules were tested every 100 randomly assigned patients: (1) 480 μg/d subcutaneously days 8 to 14; (2) 480 μg/d days 8, 10, 12, and 14; (3) 300 μg/d days 8 to 14; (4) 300 μg/d days 8, 10, 12, and 14; and (5) 300 μg/d days 8 and 12. Results All of the G-CSF schedules covered the neutrophil nadir time. Schedule 5 was equivalent to the daily schedules (schedules 1 and 3) and to the alternate da...