Mitoxantrone combined with vincristine, cyclophosphamide and fluorouracil for advanced breast cancer. A study of short-term response rate.

50 patients with advanced breast cancer were treated with the combination of Mitoxantrone 10mg/m2 IV day 2, 5-Fluorouracil 400mg/m2 IV and Cyclophosphamide 300mg/m2 IV day 3, 4, 5, 6 of each monthly cycle. 49 patients are evaluable for toxicity and 47 for efficacy after three months of treatment. Hematologic toxicity was substantial and dose-limiting, with one toxic death early in the trial. Other toxicities were moderate and manageable in this short-term study. The response rate after three cycles was 53% +/- 14% with 4 complete remissions, 21 partial remissions, 16 stable disease and 6 progressions. Using the fixed response rate hypothesis of Gehan generalised by Lee and Wesley, with an expected response rate of 60% consistent with the reported response rate of advanced breast cancer to Adriamycin containing regimens, we conclude that the combination studied is not less efficient for the induction of remissions in advanced breast cancer than comparable combinations with Adriamycin. As there is now substantial experimental and clinical evidence of reduced toxicity, mainly on the cardiac muscle, of Mitoxantrone as compared to Adriamycin, we feel that the routine substitution of the latter by the former in chemotherapy for advanced breast cancer is justifiable.

Mitoxantrone combined to vincristine, cyclophosphamide and fluorouracil in advanced breast cancer.

In our wide experience of treating advanced breast carcinoma with chemotherapy, the combination of doxorubicin (DOX), vincristine (VCR), cyclophosphamide (CPM) and fluorouracil (FU) gave a complete plus partial response rate of over 60%, with 100% alopecia and frequent cardiac toxicity depending on total dose. After the EORTC Clinical Screening Group phase II trial we have conducted an "expected difference method" comparative phase II trial using the combination DOX, VCR, CPM, FU and the combination of MTX (10mg/m2), VCR, CPM and FU on a population of 50 breast carcinoma patients similar to those taking part in the first study. The reasons for similarity of action will be presented and discussed.