Mitomycin C and vinorelbine in pretreated breast cancer.

AIMS AND BACKGROUND: Vinorelbine, a new semi-synthetic vinca alkaloid, has demonstrated high activity as a single agent in pretreated metastatic breast cancer. PATIENTS AND METHODS: To evaluate the activity of the combination vinorelbine-mitomycin C and to reduce the incidence of side effects, in particular myelotoxicity, patients with metastatic breast cancer pretreated with 1 or more chemotherapy regimens for metastatic disease were treated according to the following schedule: mitomycin C, 10 mg/m2 day 1, and vinorelbine, 25 mg/m2, days 1, 8 and 15, every 28 days. RESULTS: Twenty-seven patients were enrolled and were evaluable for activity and side effects. A total of 157 cycles were delivered (median 5 cycles per patient). There were 10 partial remissions (37%; 95% confidence interval 20-59%), 5 instances of stable disease and 12 of disease progression. Grade III-IV toxicity was mostly hematological and included thrombocytopenia (4%) and neutropenia (42%). CONCLUSION: Our results indicate that the combination of mitomycin C and vinorelbine has moderate activity in pretreated breast cancer.