Trastuzumab in combination with gemcitabine and vinorelbine as second-line therapy for HER-2/neu overexpressing metastatic breast cancer

Abstract

The aim of this study was to evaluate the safety and efficacy of combined treatment with trastuzumab (T), gemcitabine (gem) and vinorelbine (vin) as second-line therapy for HER-2 overexpressing metastatic breast cancer, pretreated with anthracyclines and/or taxanes and/or trastuzumab. Eligible patients had HER-2/neu-positive disease (IHC 2+ or 3+), performance status (PS) <or=2 and normal L-VEF. Patients were treated with weekly T (4 mg/kg on day 0, then 2 mg/kg), in combination with gem (800 mg/m(2)) and vin (25 mg/m(2)) on days 1 and 8, every 21 days. Patients were restaged every 3 cycles. A total of 30 patients (median age, 58 years; range, 41-74) were enrolled in the study. Fifteen patients were HER-2 3+ and 26 (86.7%) presented >or=2 metastatic sites. Of the patients, 7 (23.3%) had received trastuzumab as first-line therapy. Treatment was well-tolerated with grade 4 neutropenia in 6 patients, grade 3 thrombocytopenia and grade 3 anemia in 1 patient, and grade 3 asthenia in 4 patients. Fifteen patients obtained an objective response (response rate, 50%; C.I. 95%, range, 31.3-68.7%). Among the patients with HER-2/neu 3+, the response rate was 73.3%. Noteworthy were 4 objective responses observed in patients with brain metastasis. Also, 7 patients had stable disease (23.3%). Median progression-free survival was 7 months (range 5-10), and median overall survival was 15 months (range 5-33). T-gem-vin is a safe and active regimen in this subgroup of patients with poor prognosis, and the efficacy of such a schedule was particularly satisfactory in patients with HercepTest 3+.