What implications do the tolerability profiles of antiandrogens and other commonly used prostate cancer treatments have on patient care?

Abstract

Purpose: Increased awareness of prostate cancer has led to earlier initiation of therapy, and the potential for a longer duration of treatment has led to a stronger emphasis on tolerability. Historically, the mainstay of treatment of hormone-sensitive prostate cancer has been castration-based therapy, but antiandrogens are now emerging as an alternative. This article reviews the tolerability profiles of antiandrogens as well as other existing treatments for prostate cancer and examines their implications on patient care.

Methods: A search of online literature databases was conducted to identify recent articles and studies (1990-2006) that have reported adverse effects associated with treatment approaches for men with prostate cancer. The therapies reviewed here include castration, antiandrogens, a combination of castration and antiandrogens (CAB), estrogens, and chemotherapy.

Results: Castration offers significant clinical benefits when used as monotherapy or as adjuvant therapy; however, it is associated with loss of bone mineral density, and a reduction in physical activity and sexual function, which can have a negative impact on quality of life. Detrimental effects on muscle mass, fat deposition, and cognitive function have also been reported. Recent data suggest that the non-steroidal antiandrogen, bicalutamide, confers a significant overall survival benefit when used as adjuvant to radiotherapy in patients with locally advanced disease. However, the survival data for bicalutamide are not as extensive as those available for LHRH agonists. Although they do not appear to have a significant impact on sexual and physical activity, non-steroidal antiandrogens are frequently associated with gynecomastia and breast pain, and some are associated with diarrhea. Estrogens have been used in patients with androgen-independent prostate cancer; however, cardiovascular toxicity has restricted their use. In patients whose prostate cancer has become hormone-refractory, treatment options include chemotherapeutic agents, such as docetaxel and mitoxantrone.

Conclusions: It is important for physicians to discuss the adverse effects of all the available treatment options with patients so that a therapy can be selected to meet their expectations in terms of overall survival and tolerability.