Chemotherapy for androgen-independent prostate cancer.

While men with metastatic prostate cancer frequently show a good initial response to androgen ablation, few options have been available for progressive hormone-refractory prostate cancer, and survival following chemotherapy has not exceeded 9 to 12 months. The combination of prednisone and mitoxantrone has significant palliative effects on bone pain but does not extend survival. The combination of estramustine phosphate (EMP) with the taxanes paclitaxel or docetaxel produces greater than additive cytotoxicity in vivo, and phase I and II studies of taxane-based therapy demonstrate improved survival in hormone-refractory prostate cancer compared to historical controls. Docetaxel appears to have relatively high activity as a single agent and in combination with EMP. Further studies are needed to clarify the optimum dose of EMP, taking into account potential cardiovascular toxicity. Phase III studies of its combination with docetaxel are in progress.