Objective: To evaluate the efficacy and toxicity in patients with HER2 overexpressing metastatic breast cancer.
Methods: Twenty-one patients with HER2 overexpressing metastatic breast cancer entered into the study. Trastuzumab (8 mg/kg day 1, then 6 mg/kg every 21 days or 4 mg/kg, then 2 mg/kg every week) and vinorelbine (25 mg/m(2)) was given on days 1 and 8 every 21 days.
Results: Overall 56 cycles were given to the 21 patients enrolled into the study (mean 2, range 1-6). All can be evaluated. The response rate was 33.33% (7/21), one patient achieved complete response (CR), six patients achieved partial response (PR), four patients achieved stable disease (SD), ten patients achieved progressive disease (PD)]. The median time to progression was 3.5 months. One year overall survival was 33%. The major toxicity was myelosuppression and peripheral neuritis. A few patients were observed with fever and lower grade cardiac failure.
Conclusion: The combination of trastuzumab and vinorelbine is an effective and well tolerated therapy in patients with pretreated metastatic breast cancer.