Weekly Docetaxel as Second-Line Therapy for Patients with Advanced Breast Cancer Resistant to Previous Anthracycline Treatment

Abstract

This phase II trial evaluated the efficacy and toxicity of weekly docetaxel as treatment of advanced metastatic breast cancer patients resistant to prior anthracycline chemotherapy. After the first 18 patients, the initial dose (40 mg/m², 30-min i.v. infusion for 6 consecutive weeks, followed by 2-week rest) was reduced to 36 mg/m² in the remaining 17 patients due to the incidence of toxicity (28% grade 3-4 asthenia). Overall response rate was 34% (95% CI, 19-50): two complete (6%) and ten partial responses (28%) were found. The median duration of response was 6.8 months, the median time to disease progression was 8.4 months, and the median overall survival was 13.6 months (median follow-up of 11.4 months). Neutropenia was the only severe hematologic toxicity (17% of patients), whereas asthenia, nail, ocular and skin disorders were the most common nonhematologic toxicities. Only one death during further follow-up was related to toxicity (caused by pulmonary fibrosis). In conclusion, we found weekly docetaxel to be an active and safe chemotherapy regimen for patients with metastatic breast resistant to previous anthracyclines. This weekly regimen caused minimal myelosupression, while retaining significant activity against advanced breast cancer. Both factors provide attractive possibilities for the development of combination therapies incorporating weekly docetaxel. Nevertheless, the number of patients receiving either dose (40 and 36 mg/m²) which we studied is low and our results require confirmation on larger groups of patients.