What is Hormone Therapy? How is it Used for Prostate Cancer Treatment?

Question: What is Hormone Therapy? How is it Used for Prostate Cancer Treatment?

Answer:

Hormone therapy

Most prostate cancer cells are stimulated by testosterone, a primary male hormone. By eliminating testosterone from the body, prostate cancer cells drastically slow down their growth rates. A drop in testosterone levels can affect all prostate cancer cells--even those that have spread to other parts of the body, and can control prostate cancer for several years.

Hormone therapy (also known as "androgen deprivation therapy") for prostate cancer to reduce testosterone is usually achieved in one of three ways:

• Surgical castration, which removes the testicles (also known as an orchiectomy)
• Luteinizing hormone releasing hormone (LHRH) therapy
• Androgen blockage by estrogen to stop the the testicles from producing testosterone.

Castration

Ninety five percent of testosterone is produced by the testicles, so castration removes a majority of the testosterone. Surgical castration involves surgery to remove the testicles, and is not reversible. If surgical castration is performed, the adrenal glands sometimes compensate for the removal of the testicles by producing testosterone. This requires a man to continue to take testosterone blocking drugs even after a castration.

LHRH Therapies

Luteinizing hormone releasing hormone (LHRH) or an analog (similar acting substance) prevents the testicles from producing testosterone. It saves the testicles (they aren't removed) and this therapy works as well as surgical castration.

For many men, keeping their testicles makes this a good option. LHRH is usually taken orally as a tablet.

Estrogen as Androgen Blocking Therapy

With this therapy, estrogen (a female hormone) is given to men to stop the testicles from producing testosterone.

When to Select Hormone Therapy

Generally, hormone therapy is only selected to slow the growth or spread of prostate cancer that has already spread beyond the prostate. men with cancer that has returned after a radical prostatectomy or radiation therapy may also be considered for hormone therapy. Physicians may also use hormone treatment to reduce the prostate gland size so that brachytherapy, cryotherapy, or HIFU may be used.

Side Effects and Risks

Orchiectomy (surgical castration) is not reversible, and the procedure sometimes involves a hospital stay. Side effects of all types of hormonal therapy are similar and are the result of the reduced testosterone levels. These include:

• Impotence
• Hot flashes
• Weight gain
• Loss of muscle mass
• Fatigue
• Loss of sexual drive

One side effect unique to LHRH therapy is that it may at first increase tumor growth and make the symptoms worse. This is known as tumor flare.

Other side effects seen with men who receive hormonal therapy include nausea/vomiting, as well as breast swelling and tenderness.

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