Phase II study of gemcitabine plus epirubicin plus paclitaxel in metastatic breast cancer patients

Abstract

Although metastatic breast cancer is essentially incurable, patients achieving a complete response may be good candidates for long term survival. Gemcitabine, epirubicin and paclitaxel have different mechanisms of action. Therefore, we conducted this phase II study to assess efficacy and safety of gemcitabine plus epirubicin plus paclitaxel (GET) combination therapy in metastatic breast cancer. The study enrolled 21 women with pathologically confirmed and measurable metastatic breast cancer who were not previously treated with gemcitabine and paclitaxel and prior doxorubicin cumulative dosage was no more than 240 mg/m² and epirubicin cumulative dosage 360 mg/m². Median ECOG performance status was 0. Fifteen patients (71.4%) had visceral metastases and most of them had liver and lung involvement as the predominant site. Treatment schedule was as follows: gemcitabine 1000 mg/m ² was administered intravenously in 30 minutes on days 1 and 4 and epirubicin 90 mg/m² was administered intravenously 30 minutes on day 1 following gemcitabine administration and paclitaxel 175 mg/m² was administered intravenously in 3 hours on day 1 starting immediately after epirubicin. Objective response rate was 57.1% with 14.2% CR, and 42.8% PR. Median time to progression and overall survivals were 11 and 19 months respectively. Treatment of five patients was discontinued due to toxicity. Grade 3-4 neutropenia, anemia and thrombocytopenia were observed in 100%, 52.3%, and 42.8% of patients respectively. First and second dose reductions due to myelotoxicity were performed in 66.6% and 42.8% of patients respectively. Only 33.3% of patients received scheduled dose. In our study, the GET regimen has comparable efficacy to anthracycline-alkylator or anthracycline-taxane combination but requires proportionally high dose modifications due to myelotoxicity.