Mitoxantrone, 5-FU, and leucovorin in breast cancer.

Eighteen patients (17 evaluable for response) with metastatic breast cancer were treated with mitoxantrone 10 mg/m2 day 1, followed by 5-fluorouracil 375 mg/m2 day 1-5, and high-dose leucovorin 500 mg/m2 day 1-5 given every 28 days. There was one complete and four partial responses for an objective response rate of 30% and 41% stable disease. The major toxicities were hematologic and gastrointestinal. This regimen has activity in metastatic breast cancer comparable to conventional and/or standard chemotherapy regimens for advanced disease.