Treatment of metastatic carcinoma of the prostate

Disseminated carcinoma of the prostate (CaP) is a common manifestation of this disease. Metastatic CaP in the United States is seen in about 45,000 patients each year at diagnosis. At least the same number of patients who have had prior definitive treatment with surgery or radiotherapy develop evidence of metastatic disease. Hormonal management is the most important and well established treatment for patients with prostatic metastases. Orchiectomy remains the most efficient and most cost effective therapy in a rapid ablation of testicular androgens. Due to a well known psychological reaction to castration which is seen in many patients, diethylstilbestrol (DES) is a good alternative and cost effective therapy. The mode of action of DES is to suppress LH production and to slowly, indirectly, decrease serum testosterone level. In recent years, total androgen blockade (TAB) has become a widely accepted treatment option. This treatment has been shown in several clinical trials to be effective and well tolerated by the patients. A major problem with a routine use of TAB is a relatively high cost of this therapy. In a European prospective randomized trial, goserelin acetate-flutamide combination significantly increased time to progression when compared with orchiectomy alone. Patients with localized and symptomatic metastases are best treated with radiotherapy. Those with multiple sites of involvement are best treated with strontium-89 which results in a good palliation in a majority of patients. Nearly all hormonally treated patients, with metastatic CaP, eventually show tumor progression. Presently available chemotherapy is of a low effectiveness and should not be used for these patients outside of controlled clinical trials. Current research is directed to identify effective therapy for hormone refractory patients. Immunotherapy and gene therapy may be useful future therapeutic options.