Purpose: To evaluate the efficacy and toxicity of the combination of ifosfamide (IFX) and vinorelbine (VNB) as first-line chemotherapy in metastatic breast cancer (MBC).
Patients and methods: Between August 1993 and August 1995, 45 patients with untreated MBC received a regimen that consisted of IFX 2 g/m2 by 1-hour intravenous (i.v.) infusion on days 1 to 3, mesna 400 mg/m2 by i.v. bolus at hours 0 and 4 and 800 mg/m2 orally at hour 8 on days 1 to 3, and VNB 35 mg/m2 by 20-minute i.v. infusion on days 1 and 15. Courses were repeated every 28 days. During the first course only, half-dose VNB (17.5 mg/m2) was administered on days 8 and 22. The median age was 53 years and 30 patients (67%) were postmenopausal. Dominant sites of disease were soft tissue in nine patients, bone in seven, and visceral in 29.
Results: Objective responses (ORs) were recorded in 25 of 43 assessable patients (58%; 95% confidence interval, 43% to 73%). Complete remissions (CRs) occurred in six patients (14%) and partial remissions (PRs) in 19 (44%). No change (NC) was recorded in 10 patients (23%) and progressive disease (PD) in eight patients (19%). The median time to treatment failure was 12 months and the median survival duration 19 months. Myelosuppression was the limiting toxicity, mainly leukopenia in 32 patients (74%). In contrast, anemia and thrombocytopenia were mild. Other significant toxicities included peripheral neuropathy in nine patients (21%), constipation in 15 (35%), and myalgias in 11 (26%).
Conclusion: IFX/VNB is an active combination against MBC with moderate toxicity and deserves further evaluation.