Twenty-three patients with disseminated carcinoma of the breast were treated with a combination chemotherapy protocol employing cyclophosphamide, vincristine sulfate, methotrexate, fluorouracil, and prednisone. Ten of these patients had at least a partial response (greater than 50% reduction in tumor mass), a rate not dissimilar to the employment of single agents. However, of particular significance is the fact that four of the responses were complete remissions. This is a unique occurrence, since in a review of 1,590 patients treated with single agents only a single complete response is cited. Response did not seem to be related to prior therapy and did appear to correlate with increased survival. Toxic reaction was generally mild and readily reversible. Virtually all patients were treated and managed on an outpatient basis.Carci noma of the breast, by vir¬ tue of incidence and mortality, is the single most significant neoplastic disease occurring in women in the United States. The magnitude of this entity, which by itself accounts for 25% of all carcinomas in women and produces roughly 67,000 new cases per year, is most cogently underscored by