Background: Gemcitabine and vinorelbine are active agents for the treatment of metastatic breast cancer. Prolonged infusion of gemcitabine can result in higher levels of active metabolites compared to shorter administration. This phase II trial was initiated to evaluate the efficacy and tolerability of gemcitabine as prolonged infusion in combination with vinorelbine in anthracycline and/or taxane pretreated patients with metastatic breast cancer.
Patients and methods: Patients who had received one prior line of chemotherapy for metastatic disease were treated with gemcitabine (350 mg/m2 as 4 h infusion) and vinorelbine (25 mg/m2 on days 1 and 8. Treatment was repeated every 3 weeks for a maximum of six cycles.
Results: Of 26 patients enrolled, 84% had received prior anthracycline treatment and 50% prior taxane therapy. In total, one complete and six partial responses were achieved, accounting for an overall response rate of 30.4%. The clinical benefit rate was 47.8%. Median duration of response and median time to progression were 7.3 months and 4.6 months, respectively. Median overall survival was 14.5 months. Although the predominant toxicity was myelosuppression with grade 3/4 neutropenia in 42% of patients, few neutropenic complications resulted. Non-hematological toxicity was generally moderate. Most common non-hematologic toxicities were nausea, vomiting, alopecia, peripheral neuropathy and elevation of liver enzymes.
Conclusion: Gemcitabine as prolonged infusion and vinorelbine are a safe and effective combination treatment in anthracycline and/or taxane pretreated patients. Approximately 47.8% of patients derived clinical benefit from treatment. This regimen represents a therapeutic option for patients receiving second-line therapy for metastatic breast cancer.