Gemcitabine Plus Docetaxel Versus Docetaxel Alone in Locally Advanced, Recurrent, or Metastatic Breast Cancer Pre-treated with Anthracycline

Purpose: Use of gemcitabine plus docetaxel combination in metastatic breast cancer is motivated by the different mechanisms of action of the drugs, non-overlapping toxicity profiles, and good single-agent activities of both drugs in treatment-naive and anthracycline-pretreated patients. The purpose of this study was to evaluate the efficacy and toxicity of combined gemcitabine and docetaxel versus docetaxel alone in patients with advanced breast cancer. Patients and Methods: Seventy patients with locally advanced, recurrent or metastatic breast cancer were enrolled, of whom fifty-one had received prior anthracycline chemo- therapy in the adjuvant setting and nineteen for metastatic disease. Treatment consisted of either gemcitabine 1000 mg/m2 on days 1 and 8 plus docetaxel 75mg/m2 on day 1, or docetaxel alone 100mg/m2 on day 1, with cycles repeated every 21 days for a maximum of 10 cycles. Results: The overall response rate was 57.1%, including 11.4% complete response rate in combined therapy versus 34.3% with 5.6% in single agent therapy (p=0.026, p=0.039), respectively. The median duration of response was 8.75 months in combined therapy versus 6.5 months in single agent therapy (p=0.033). The median time to progression was 7.5 months in combined therapy versus 5.6 months in single agent therapy (p=0.041).The median overall survival was 15.5 months in combined therapy versus 11.5 months in single agent therapy (p=0.049). Myelosuppression was commonly observed grade 3-4 neutropenia occurred in 48.5% in combined therapy versus 40% in single agent therapy. While febrile neutropenia occurred in only 8.5% in combined therapy versus 5.7% in single agent therapy. Grade 3 anemia was seen in only 5.7% in both treatment groups and grade 3-4 thrombocytopenia was ob- served in 11.4% in combined therapy versus 8.5% in single agent therapy. Non-hematologic toxicity was usually mild to moderate and manageable in both treatment groups. Conclusion: Gemcitabine-docetaxel combination exhibited encouraging synergistic activity and tolerable toxicity if compared with docetaxel alone in advanced breast cancer.