Thirty patients with advanced breast cancer, previously treated with anthracycline and 5 fluorouracil in bolus administration, were evaluated with a chemotherapy regimen generally used in head and neck cancer. Treatment schedule consisted of: cisplatin 100 mg/m2 on d 1 and 5 fluorouracil 1000 mg/m2 continuous infusion on d 2-3-4-5 every 21 d. With all measurable lesions and 27 evaluable patients, the response rate was 29% (95% confidence interval: 12-47%), with 5 complete responses (3 soft tissue - 2 lung) and 3 partial responses (1 lung - 2 liver). The median duration of response is 4.5 months (range 2-11 months). The 30 patients (93 courses) are evaluable for toxicity. Hematologic toxicity was mild: anemia 68% grade 0, neutropenia 68% grade 0 and thrombocytopenia 83% grade 0. Nausea and vomiting were severe 83% grade 3 + 4 at d 1. Others side effects were mild including 5/91 mucositis grade 2 + 3, peripheral neuropathy 1/31 grade 2 and 2/91 reversible rise in serum creatinine greater than 1.5 mg/dl.