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

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+.