Phase II study of combined vincristine, adriamycin, cyclophosphamide, and methotrexate with citrovorum factor factor rescue in metastatic breast cancer.

Fifty patients with metastatic breast cancer were treated with 8-day courses of vincristine (1 mg iv, Day 1), adriamycin (50 mg/m2 iv, Day 1), cyclophosphamide (100 mg/m2 orally, Days 1-8), methotrexate (200 mg iv by 3-hour infusion, Day 8), and citrovorum factor rescue (15 mg in 12, 18, and 24 hours after methotrexate, Day 8) at 3-4-week intervals. Forty-two patients had previously received treatment with hormones and 17 patients had received chemotherapy. Fifteen patients achieved a complete remission (CR) and 24 patients a partial remission (PR). There was a significant correlation between the response and the number of metastatic organs (0.01 less than P less than 0.02). The response rate was roughly uniform irrespective of the organ predominantly involved (0.2 less than P less than 0.3). The remission duration was significantly longer for the patients with CR compared with that for the patients with PR (0.001 less than P less than 0.01). The patients who achieved CRs and PRs survived significantly longer than the patients with no change and progressive disease (P less than 0.001). The toxic effects of the treatment were acceptable and no drug-related deaths occurred.