A phase II study of carboplatin and etoposide as salvage polychemotherapy in metastatic, infiltrating breast carcinoma was carried out with 25 multiply pretreated patients. Six of 25 patients (24%) had a partial response that lasted an average of 3.5 months; of the six responders, four had undergone either four or five previous chemotherapeutic treatments. Eight of 25 patients (32%) had stable disease, and 11 (44%) manifested disease progression. The median survival from time of entry to the salvage protocol was 8 months. There were treatment responses in lung, chest wall, liver, and skeleton. The most common side effects were leukopenia (68% of 25 patients), thrombocytopenia (56%), anemia (40%), fever (28%), and weakness (16%). Carboplatin combined with etoposide may be an effective and tolerable salvage regimen in advanced breast cancer.