Purpose: To assess the activity and safety of combined folinic acid (FA), 5-fluorouracil (5-FU) and mitomycin C (MMC) in metastatic breast cancer patients previously treated with at least two chemotherapy regimens.
Patients and methods: A total of 104 consecutive patients were enrolled for treatment with FA 100 mg/m(2) plus 5-FU 400 mg/m(2) i.v. on days 1-5, and MMC 3 mg/m(2) on days 3-5 (FFM). The cycles were repeated every 21 days until progression, severe toxicity or patient refusal.
Results: Of the 104 patients, 96 were evaluable for response and toxicity. The overall response rate was 43% (95% confidence interval 32.8-53.2%); 40 patients achieved stable disease (42%) and 15 progressed (15%). In a retrospectively defined subgroup of patients with clinical resistance to taxanes (12 patients) or anthracyclines (14 patients), the response rate was 42%. The median time to progression was 8 months (3-18 months), and the median overall survival was 10.5+ months (2-36 months). The most common treatment-related adverse events were stomatitis, neutropenia, nausea/vomiting and diarrhea. Stomatitis, neutropenia and thrombocytopenia were the only grade 4 treatment-related adverse events, and occurred in no more than 3% of patients.
Conclusion: The tested FFM regimen seems to offer a valid option for patients with metastatic breast cancer who have been pretreated with two or more chemotherapeutic lines or who have failed on regimens containing anthracyclines or taxanes.