Hormonal therapy for locally advanced prostate cancer

Abstract

A patient with locally advanced prostate cancer (stages C and D1) has a poor prognosis with a high risk of developing and dying of distant metastases. Hormonal therapy is the major form of systemic therapy for metastatic (stage D2) prostate cancer. The most commonly used forms of hormonal therapy are orchiectomy, diethylstilbestrol, and luteinizing hormone releasing hormone, agonists that prevent the stimulation of tumor cells by testosterone. They produce a 60%-80% symptomatic or objective response rate, but their ability to prolong overall survival remains uncertain. Surgical adrenalectomy, hypophysectomy, and pharmacologic adrenal suppression prevent the clinically less significant adrenal androgen stimulation of tumor cells. Antiandrogens competitively inhibit the interaction between androgens and cytosolic androgen receptors. Complete androgen blockade (luteinizing hormone releasing hormone agonist and antiandrogen) was initially espoused to be superior to single-agent hormonal therapy, but preliminary results from a multigroup randomized trial suggest that it has only a minimal advantage. The benefit of hormonal therapy in stages C and D1 prostate cancer at the time of diagnosis has not been clearly established. Available studies are few, and most often they are uncontrolled or include only small numbers of patients. However, they suggest that the early use of hormonal therapy prolongs disease-free survival but does not prevent ultimate disease progression or prolong overall survival. Hormone receptor assays may be helpful in the selection of patients who would benefit from early hormonal therapy.