Mitoxantrone, fluorouracil plus L-leucovorin, and vinorelbine in pretreated advanced breast cancer.

The combination chemotherapy including mitoxantrone, fluorouracil and leucovorin has proven to be effective and well-tolerated in advanced breast cancer (ABC). No data are available on the association with navelbine, a new vinka alkaloid, which has demonstrated high activity in ABC. The trial was designed to evaluate feasibility and efficacy of the association of vinorelbine to mitoxantrone, fluorouracil and L-leucovorin in patients who failed a previous regimen for ABC or who relapsed within 6 months of adjuvant chemotherapy. The schedule was as follows: mitoxantrone 6 mg/m2 days 1 and 8; L-leucovorin 250 mg/m2 days 1 and 8, fluorouracil 600 mg/m2 days 1 and 8, vinorelbine 25 mg/m2 days 1 and 8, cycles being repeated every 21 days. Twenty-five patients were enrolled and are evaluable for response and side effects. One hundred cycles of therapy have been delivered (median/patient, 4 cycles). In 41 cycles a delay was required and in 38 cycles it was necessary to administer granulocyte colony-stimulating factor for neutropenia. Seven partial remissions (28%; 95% confidence interval, 12-49%), 10 stabilizations of disease and 8 progressions were observed. Although grade 4 neutropenia was observed in 44% of the patients, no grade 3-4 infections were observed. Nonhematologic toxicities were mild or moderate and included alopecia, mucositis and phlebitis. In conclusion, the schedule employed, although correlated with a moderate activity, does not seem to be superior to other regimens with mitoxantrone, fluorouracil, and leucovorin.