Hormone Therapy

When cancer has spread beyond the prostate gland, androgen deprivation therapy (ADT), or hormone therapy, is often recommended as the initial treatment. The rationale for using hormone therapy for advanced prostate cancer is that male hormones (androgens, such as testosterone) promote or stimulate tumor growth. When deprived of male hormones, the cancerous cells of the prostate gland (as well as normal cells) die and the prostate gland shrinks in size. Hormone therapy is effective against cancer cells within the prostate and for any cancer cells that may have spread outside the gland.

Most men with advanced prostate cancer initially respond well to hormone therapy, but most have recurrent disease within two years. At this point, the cancer is termed hormone-resistant, meaning that ADT alone is no longer effective. Once this occurs, secondary hormone therapy is considered. Even when prostate cancer becomes resistant, some form of hormone therapy is continued because at least a portion of the cancer cells may still respond to the removal of androgens. Eventually, even with secondary hormone treatment, nearly all men with advanced prostate cancer stop responding to all forms of hormone treatment. This situation is referred to as hormone refractory prostate cancer (HRPC). The next step in treatment is determined by an individual's characteristics and preferences, and often includes chemotherapy.