Trastuzumab plus gemcitabine and cisplatin chemotherapy for HER2/neu-overexpressing breast cancer with visceral metastasis

1109 Background: Trastuzumab provides significant clinical benefits in HER2-positive metastatic breast cancer patients when administered in combination with chemotherapy. This single arm phase II trial evaluated the safety and efficacy of adding trastuzumab to a combination of gemcitabine and cisplatin as 2nd line in patients with visceral metastasis from HER2-positive breast cancer. Methods: Patients with previously treated stage IV (with visceral metastasis) from HER2-positive breast cancer received up to six 21- day cycles of gemcitabine 1,000 mg/m2 (days 1 and 8) and cisplatin 35 mg/m2 (days 1 and 8) as well as trastuzumab 4 mg/kg intravenously followed by 2 mg/kg/week i.v. until progression. Results: Forty patients were recruited, all of whom had previously received chemotherapy (24 pre-treated with taxanes, 16 pre-treated with anthracyclines). A median of six cycles of the study treatment was delivered. The overall objective response rate of 60% (24/40 patients) including 8 patients achieving a comp...