A total of 44 women with advanced breast cancer who had failed first- and second-line chemotherapy were given combination chemotherapy consisting of folinic acid (FA), 5-fluorouracil (5-FU) and mitomycin C (MMC). The treatment schedule was: 200 mg/m2 FA and 400 mg/m2 5-FU given i.v. over 2 h for 5 days plus 5 mg/m2 MMC given i.v. on days 3-5; in 19 patients with an Eastern Cooperative Oncology Group (ECOG) performance status of 3-4 and bone marrow depression, the MMC dose was 3 mg/m2 given i.v. on days 3-5. In all, 41 patients were evaluable for response; 15 had a partial remission (PR), 18 had stable disease (SD), and 8 showed progressive disease (PD). The median response duration was 6 months and the median survival was 10 months. Toxicity was mild and consisted mainly of stomatitis, diarrhea, and leukopenia. A rapid improvement in performance status was noted in responding patients. A striking result was the reduction of analgesics in most cases and their complete withdrawal in responding patients. This combination chemotherapy achieved satisfactory effectiveness and improved the quality of life of patients.