[Docetaxel]

To date, in cases of advanced or recurrent breast cancer, combination chemotherapy including anthracycline have been used for 1st-line treatment. Mitomycin C and oral 5-FU were used for cases refractory to such treatment, but the response rate was not satisfactory. Docetaxel is one of the most promising drugs to have emerged in recent years, with phase II studies in previously untreated metastatic breast cancer indicating a high overall response rate of approximately 60%, in the refractory cases for anthracyclines, indicating an overall response rate of 40% using docetaxel at 75 to 100 mg/m2 as a 1-hour intravenous infusion every 21 days. In Japan, the overall response rate was reported as about 50% using single docetaxel given at 60 mg/m2 every 21 days. The dose-limiting toxicity is myelosuppression, which is dose-but not schedule-dependent. In most published studies, there is a 90-95% incidence of grade 3 or 4 neutropenia when docetaxel is administered every 3 weeks. In recent studies, for the purpose of reducing the severity of myelosuppression, weekly docetaxel seems to be an effective and feasible treatment for advanced or recurrent breast cancer.