08-01-2008, 03:23 PM
TREATMENT OF METASTATIC (STAGE IV) PROSTATE CANCER ” When cancer has spread beyond the prostate gland, androgen deprivation therapy (ADT) is usually recommended as the initial treatment. Metastatic prostate cancer is not considered a curable condition. However, treatment can prolong life, delay the progression of the cancer, relieve cancer-related symptoms, and improve quality of life.
Initial androgen deprivation therapy ” The rationale for using ADT 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. ADT is effective against cancer cells within the prostate gland and for any cancer cells that may have spread outside of the prostate.
There are several ways in which ADT can be accomplished:
Orchiectomy ” ADT can be accomplished by removing the testicles, where most of the body's androgens are produced (this operation is called an orchiectomy). The penis and scrotum (skin pouch in which the testicles are located) remain intact.
GnRH agonists ” An alternate way to accomplish ADT is to take a medication that disrupts androgen production in the body. These drugs work by interfering with gonadotropin releasing hormone (GnRH), which is the chemical that regulates the amount of androgen that a man's testicles make under normal conditions. Drugs in this class include leuprolide (Lupron®) and goserelin (Zoladex®). These are given by injection.
Guidelines for treatment of men with advanced prostate cancer from the American Society of Clinical Oncology (ASCO) recommend either orchiectomy or a GnRH agonist as the initial form of hormone therapy [1] . GnRH agonists and orchiectomy are similarly effective in men with advanced prostate cancer, and they share a similar side effect profile (see "Side effects of ADT" below). However, there are some differences which may influence an individual man's choice of