Comparison of adjuvant chemotherapy with methotrexate and fluorouracil with and without cyclophosphamide in breast cancer patients with one to three positive axillary lymph nodes

Background: Alkylating agents administered as single agents or in combination with antimetabolites or anthracyclines delay the appearance of metastases and prolong the survival of breast cancer patients after surgery. Purpose: This phase Ill clinical trial was designed to evaluate the therapeutic efficacy and toxicity of the alkylating agent cyclophosphamide in combination with the antimetabolites methotrexate and fluorouracil adjuvant to breast cancer surgery. Methods: This study consisted of 255 breast cancer patients (a) with one to three histologically positive axillary lymph nodes and either no detectable primary tumor or operable primary tumors 5 cm or less (T0-T2) (95% of the patients) or (b) with tumors larger than 5 cm (T3) and with negative axillary nodes. Patients were randomly allocated to receive either methotrexate (60 mg/[m.sup.2]) and fluorouracil (600 mg/ [m.sup.2]) (MF) intravenously on days 1 and 8 every 28 days for eight cycles or cyclophosphamide (100 mg/[m.sup.2]) orally on days 1-14 plus MF (CMF) every 28 days for the same duration. Median follow-up was 7.8 years, and maximum follow-up was 13 years. Results: There were no statistically significant differences in time to treatment failure or overall survival for patients treated with MF or CMF. At 8 years after completion of treatment, time to treatment failure was 55% (95% confidence interval [CI] = 50%-60%) and 59% (95% CI = 54%-64%) and overall survival was 69% (95% CI = 65%-73%) and 67% (95% CI = 62%-72%) for MF-and CMF-treated patients, respectively. The hazard ratios (MF to CMF) for time to treatment failure and for survival, estimated with a proportional hazards model, were 1.02 (95% CI = 0.69-1.50) and 0.87 (95% CI = 0.56-1.34), respectively. Myelosuppression was significantly greater (P