Full Dose Paclitaxel Plus Vinorelbine as Salvage Chemotherapy in Anthracycline-Resistant Advanced Breast Cancer: A Phase II Study

This phase II trial studied the efficacy and toxicity of full dose paclitaxel plus vinorelbine, as salvage chemotherapy in patients with metastatic breast cancer resistant to anthracyclines. Patients received vinorelbine (30 mg/m²) followed 1 hour later by full dose paclitaxel (175 mg/m²) every 3 weeks for a maximum of 8 cycles or until disease progression. Because of the heavy pretreatment of the patients, prophylactic granulocyte-colony stimulating factor (5 μg/kg) was administered daily for 5-10 days. To minimize potentially cumulative neurotoxicity due to both agents, amifostine was given prior to chemotherapy. Thirty-four patients: 8 with tumors primary resistant and 26 with tumors recurring within 3-6 months after anthracycline treatment, were evaluable for efficacy and toxicity. Objective responses occurred in 11 patients (32%; 95% confidence interval (CI): 16.3-47.7%), all partial responses. Responses were observed in lung and liver. The median response duration was 4 months (range 3-7), median time to progression was 5 months (range 3-9) and median overall survival was 8 months (range 4-24). Neutropenia was dose limiting (35% grade 3-4 toxicity). The left ventricular ejection fraction, measured and followed in 18 patients, fell less than 20% below baseline level in 9 patients (50%), but only one patient developed congestive cardiac failure. The paclitaxel-vinorelbine regimen was moderately tolerated and moderately effective in poor prognosis breast cancer patients with visceral metastases and tumors resistant to anthracyclines. The combination at these doses and schedules should be considered in the design of regimens for advanced breast cancer.