Evaluation of single-drug versus multiple-drug chemotherapy in the treatment of advanced breast cancer.

Fifty-one postmenopausal patients with advanced breast cancer were randomized to receive either cyclophosphamide given continuously or cyclophosphamide given continuously with methotrexate, 5-fluorouracil, vincristine, and prednisone given intermittently. The results with the multiple-drug therapy were significantly better than with the single-drug therapy, both with regard to percentage (63% versus 25%) and median duration (400 versus 210 days) of objective response. Toxicity was moderately increased with the combination as compared to the single-drug treatment.