Docetaxel as single-agent therapy in metastatic breast cancer: clinical efficacy

The potential importance of docetaxel as a chemotherapeutic agent for the treatment of metastatic breast cancer has been documented in approximately 575 patients enrolled in phase II clinical studies in North America, Europe, and Japan. First-line treatment with docetaxel 100 mg/m2 intravenously over 1 hour every 3 weeks produced objective responses in 59% of patients (intent-to-treat). In patients with anthracycline-resistant disease (disease that responded initially but then progressed or relapsed during treatment with an anthracycline), an overall intent-to-treat response rate of 41% was achieved. A 37% response rate was observed in anthracycline-refractory patients (those who had never achieved an objective response to anthracycline-based chemotherapy). Febrile neutropenia is the major dose-limiting toxicity of docetaxel; the neutropenia nadir typically has an early onset and short duration, with rapid recovery of the neutrophil count. Other hematologic effects are rare. Skin and hypersensitivity reactions can be minimized by premedication with corticosteroids. Reversible fluid retention, related to the cumulative dose of docetaxel, is also lessened by corticosteroid prophylaxis. In summary, docetaxel has shown impressive antitumor activity in the treatment of metastatic breast cancer, including the challenging population of patients whose disease progressed during treatment with an anthracycline or anthracenedione. Most of the adverse events related to docetaxel use can be circumvented or ameliorated by careful patient selection and routine premedication with corticosteroids, and improved methods of managing side effects are being actively studied. Docetaxel is thus expected to play an increasingly prominent role in the management of patients with metastatic breast cancer.