Treatment of advanced breast cancer with mitomycin C combined with vinblastine or vindesine.

Mitomycin C together with either vindesine or vinblastine was given to 48 patients with previously treated advanced breast cancer. Thirteen (35%) of the 37 evaluable patients had a complete (one patient) or partial (12 patients) response. Overall median duration of response was 189 days (range, 90-700 days). Fifteen patients received mitomycin C and vindesine with six responses (40%) and a median response duration of 247 days (range, 162-700 days). Twenty-two patients received mitomycin C and vinblastine with seven responses (32%) and median response duration of 164 days (range, 90-330 days). Response duration for patients treated with mitomycin C plus vindesine was longer than that associated with mitomycin C plus vinblastine (p = 0.09). Significant toxicity included myelosuppression and neurologic symptoms, but was uncommon (less than 10% of patients). Therefore, the combination of mitomycin C and a vinca alkaloid appears to be useful in far-advanced refractory breast cancer.