Hormone therapy involves attempting to stop your body from producing the male sex hormone testosterone which can stimulate the growth of cancer cells. This type of therapy can also block hormones from getting into cancer cells. Sometimes doctors use a combination of drugs to achieve both. In most men with advanced prostate cancer, this form of treatment is effective in helping both shrink the cancer and slow the growth of tumors. Sometimes doctors use hormone therapy in early-stage cancers to shrink large tumors so that surgery or radiation can remove or destroy them more easily. In some cases, hormone therapy is used in combination with radiation therapy or surgery. After these treatments, the drugs can slow the growth of any stray cancer cells left behind.
Some drugs used in hormone therapy decrease your body’s production of testosterone. The hormones — known as luteinizing hormone-releasing hormone (LH-RH) agonists — can set up a chemical blockade. This blockade prevents the testicles from receiving messages to make testosterone.
Drugs typically used in this type of hormone therapy include leuprolide (Lupron) which is injected under your skin once every three or six months. You can receive treatment for a few months, a few years or the rest of your life, depending on your situation.
Other drugs used in hormone therapy block your body’s ability to use testosterone. A small amount of testosterone comes from the adrenal glands and isn’t suppressed by LH-RH agonists.
Simply depriving prostate cancer of testosterone usually doesn’t kill all of the cancer cells. Within a few years, the cancer often learns to thrive without testosterone. Once this happens, hormone therapy is less likely to be effective. However, several treatment options still exist. To avoid such resistance, intermittent hormone therapy programs have been developed. During this type of therapy, the hormonal drugs are stopped after your PSA drops to a low level and remains steady. You will need to resume taking the drugs if your PSA level rises again.
Side effects of hormone therapy can include:
- Breast enlargement
- Reduced sex drive
- Erectile dysfunction
- Hot flashes
- Weight gain
- Reduction in muscle and bone mass
Certain hormone therapy medications can also cause:
- Liver damage