A five-drug combination in the treatment of metastatic breast cancer.

The five-drug combination of fluorouracil imidazole carboxamide dimethyl triazeno, vincristine, bis-chloroethyl nitrosourea, and prednisone (FIVB + P) was given to 120 women with metastatic breast cancer. Of 114 evaluable patients, complete response was seen in 12 and partial remission in 39. Complete or partial remission was documented a) in 21 of 59 patients who had had extensive prior chemotherapy and prednisone, b) in 15 of 33 patients who had had prior chemotherapy but no prior prednisone, and c) in 15 of 22 patients who had received no prior systemic treatment for breast cancer. The regimen was well tolerated, the main side effects being hemopoietic suppression, short duration nausea and vomiting, and alopecia. The FIVB + P regimen is a useful and acceptable second or third line treatment for patients with metastatic breast cancer. There is evidence that this treatment program provides a non-cross-resistant regimen to many chemotherapy combinations currently in use in breast cancer. The high activity in previously untreated patients offers a further option for cycling of multiple agents in order to gain better disease control in patients with advanced breast cancer.