Intensification of Adjuvant Chemotherapy: 5-Year Results of a Randomized Trial Comparing Conventional Doxorubicin and Cyclophosphamide With High-Dose Mitoxantrone and Cyclophosphamide With Filgrastim in Operable Breast Cancer With 10 or More Involved Axillary Nodes

PURPOSE: To determine whether intensifying the dose of adjuvant chemotherapy improves the outcome of women with primary breast cancer and 10 or more involved axillary nodes. PATIENTS AND METHODS: Patients (n = 150) were randomized to receive either four cycles of standard doxorubicin 60 mg/m2 plus cyclophosphamide 600 mg/m2 every 3 weeks (arm A) or four courses of intensified mitoxantrone 23 mg/m2 plus cyclophosphamide 600 mg/m2, with filgrastim 5 g/kg/d from days 2 to 15, every 3 weeks (arm B). Disease-free survival (DFS), distant disease-free survival (DDFS), and overall survival (OS) were determined using life-table estimates. RESULTS: There were no significant differences in DFS (P = .44), DDFS (P = .67), or OS (P = .99) between the two groups at 5 years; DDFS was 45% (arm A) versus 50% (arm B), and DFS was 41% versus 49%, respectively. Five-year survival was similar in both arms (61% v 60%, respectively). Failure to note an intergroup difference in outcome was unrelated to relative dose-intensity. An...