Chemotherapy for prostate cancer

Androgen deprivation therapy remains the mainstay of therapy for patients with advanced prostate cancer and for selected patients with localized prostate cancer. Androgen deprivation therapy is the model of target-based therapies in this disease. Although it is clear that other target-based therapies need to be developed, cytotoxic chemotherapy is emerging as an effective form of treatment for men with prostate cancer. The early studies combining mitoxantrone plus a corticosteroid demonstrated that chemotherapy could be given to men with symptomatic hormone-refractory prostate cancer with minimal toxicity, and significant palliation could be provided. Since then, it has been recognized that estramustine, when combined with a variety of microtubular inhibitors, is very active in hormone-refractory prostate cancer. Doublets combining estramustine plus a taxane seem to be the most active. Although it appears that estramustine may add some activity to taxanes, the mechanism of its activity is uncertain, and its overall value is similarly questioned, particularly in light of its significant toxicity. Regimens that omit estramustine are being explored (ie, either taxane alone or taxane plus biologic agents). In addition, triplet therapy (combining estramustine plus a taxane plus a third drug, such as carboplatin or etoposide) is being explored. Finally, the utility of chemotherapy is beginning to be explored in the context of earlier disease in the neoadjuvant, adjuvant, or serologically relapsing group of patients. Data from these studies are just beginning to be gathered.