Twenty-five patients with metastatic breast cancer in progression after prior chemotherapy +/- hormonotherapy were treated with etoposide 50 mg/m2 i.v. days 1 to 5 every 21 days and mitomycin-C 10 mg/m2 i.v. day 1 every 42 days. A partial response (PR) occurred in 10 patients with an overall response rate of 40% (47% when only the 21 patients evaluable after 3 courses or more were considered). The median duration of PR was 10.5 months (range 3-31). The soft tissue metastatic sites were the most responsive. Toxicity was mild.