PS 08. Androgen Deprivation therapy for prostate cancer and the impact on male sexual function

The importance of androgens in the maintenance of homeostasis in a male has been well established. Even in the earliest stages of embryological development, androgens play a vital role in sex differentiation. This is most evident in patients who lack androgen receptors or have decreased androgen sensitization, leading to sexual dimorphism. The most significant impact of androgen in uro-oncology was from Charles B. Huggins's work in 1940s when he reported that prostatic epithelium underwent atrophy when androgen hormones were greatly reduced and significant improvements occurred in patients with far advanced prostate cancer after castration. Androgen deprivation therapy (ADT) has since been a powerful treatment option for those with advanced prostate cancer. The main goal of ADT is to block the interaction between androgens and prostate, either by decreasing androgen production, blocking androgen receptors, or a combination of both. The most commonly used therapeutic strategy is to decrease testosterone production by means of castration, either medically or surgically. It is estimated that more than 189,000 new cases of prostate cancer are diagnosed each year in USA and the new cases were 217,730 in 2010. About ten percent of patients with prostate cancer will receive ADT at some point during their disease course.

Despite its effectiveness in battling prostate cancer, ADT is a double-edged sword as its side effects are numerous. Since testosterone regulates several aspects of sexual function, castration will cause significant side effects involving erectile function, anatomical changes in the male genitalia, libido, and ejaculation. Therefore ADT has a deleterious impact on the patient's quality of life, especially in young patients with good pre-treatment sexual function. Currently we do not have a consensus regarding the diagnosis and management of sexual dysfunction in these patients. Intermittent androgen deprivation therapy is a promising alternative to minimize these side effects. The concept of penile rehabilitation is a good therapeutic strategy to prevent permanent penile morphologic changes due to lack of testosterone. The non-surgical management for erectile dysfunction that is generally offered first may only be effective in a small amount of individuals. A recent study showed that surgical therapy with penile prosthesis implantation can still provide high satisfactory results in this particular group of patients.