Phase II of doxorubicin/taxol in metastatic breast cancer. Argentine Multicenter Taxol Group.

PURPOSE: To assess the response rate, survival, and toxicity of Taxol (paclitaxel) as 1-h infusion plus doxorubicin as first-line treatment for patients with metastatic breast cancer (MBC). PATIENTS AND METHODS: Seventy-six patients with untreated MBC were recruited. All of them had measurable disease and were evaluable for toxicity. Fifty-five percent of the patients had visceral involvement. The dose of doxorubicin was fixed at 50 mg/m2 as a short intravenous infusion, followed by 200 mg/m2 of Taxol as a 1-h intravenous infusion. Doxorubicin was administered during the first seven cycles, continuing with Taxol only up to a maximum of ten cycles. RESULTS: Neutropenia was the most important toxicity: 30% grade 3 and 18% grade 4. Only 2 patients showed a decrease in the left ventricular ejection fraction (LVEF) which caused discontinuing the treatment. No clinical congestive heart failure (CHF) was observed. Seventy-four patients were eligible for response evaluation: 10 (14%) achieved complete response (CR) and 46 (62%) achieved partial response (PR). The mean duration of response was 13.47+/-1.35 months (95% confidence interval (CI): 10.82; 16.12) and the mean survival was 21.50+/-1.42 months (95% CI: 18.72; 24.29). CONCLUSION: The overall response (OR) rate was 76%. No CHF was assessed and 2 patients stopped treatment due to LVEF decrease. Although doxorubicin 50 mg/m2 followed by Taxol 200 mg/m2 in 1-h intravenous infusion presents a toxicity profile which demands a close follow-up, it represents a convenient outpatient schedule with similar activity rate compared to longer Taxol infusions.