Focus on Hormone Therapy
Hormones are produced by glands in the body and circulated through the bloodstream. Most prostate cancer cells thrive on male hormones (androgens) such as testosterone for growth. Most (90%-95%) of these androgens come from the testicles8 while the rest are from the adrenal glands. Hormone therapy is used to keep cancer cells from getting the male hormones they need to grow. It plays an important role in managing prostate cancer, controlling both localized tumors and those that have spread to other areas of the body.
When prostate cancer begins spreading to other areas of the body, treatment may shift to hormone therapy, which reduces the testosterone that nourishes the prostate gland. Depleting the testosterone may help reduce symptoms while preventing further growth.7
Hormonal therapy causes the cancer to shrink in 85%-90% of patients with advanced cancer, but it does not cure it. Treatment duration varies and may not affect all prostate cancer cells. Cells that don’t respond to this therapy are called “hormone-independent” or “androgen-insensitive” cells.7
Hormone Therapy Options8
Surgery or medication is used to reduce or eliminate male hormones such as testosterone.
- Surgery. Testosterone levels can be reduced by removing the testes during what is called an orchiectomy. This involves surgically opening the scrotum to free the blood vessels and nerves. Then the testicles are removed from surrounding tissue.
- Medication. The second option is chemical, or medical, castration.
Medications are used to disrupt the body’s normal production or use of testosterone,
- Gonadotropin-releasing hormone (GnRH) agonists: The most common way to lower production of male hormones, these drugs, such as Trelstar®, shut down the secretion of GnRH from the brain that causes the testes to produce testosterone.
- Estrogens: Estrogen therapy blocks the secretion of GnRH; the pituitary is not stimulated and other organs like the testes do not produce testosterone.
- Antiandrogens: Antiandrogens work to block androgen receptors in cells, disrupting androgen actions including cell proliferation.
- Gonadotropin-releasing hormone antagonists: GnRH antagonists reversibly bind to GnRH receptors in the pituitary to reduce the release of gonadotropins and, in turn, the production of testosterone.23
Hormone therapy is a treatment, not a cure. It does relieve the symptoms of the disease and may keep it from progressing. Treatment options should be discussed with your doctor.
- National Comprehensive Cancer Network. NCCN Treatment Summaries for People with Cancer. Prostate Cancer – Overview http://nccn.com/prostate_cancer_overview.aspx. Accessed February 16, 2010
- Cancer Facts & Figures 2009. American Cancer Society.
- Prostate Cancer Foundation. FAQs About Prostate Cancer. http://prostatecancerfoundation.org/site/c.itIWK2OSG/b.4983495/k.5C76/About_Prostate_Cancer.htm. Accessed February 16, 2010.
- Zelefsky M, Eastham JA, Sartor O, Kantoff P. Cancer of the Prostate. In: DeVita VT, Lawrence TS, Rosenberg SA, eds. Cancer Principles and Practice. 8th ed. Philadelphia, PA. Lippincott, Williams & Wilkins. 2008.
- SEER. http://seer.cancer.gov/statfacts/index.html. Accessed December 8, 2010.
- National Cancer Institute. Early Prostate Cancer. http://cancer.gov/cancertopics/factsheet/Detection/early-prostate. Accessed February 16, 2010.
- Report to the Nation on Prostate Cancer: A Guide for Men and their Families. Prostate Cancer Foundation. 2005. Santa Monica, CA.
- ACS Detailed Guide: Prostate Cancer. Hormone (androgen deprivation) Therapy. www.cancer.org. Accessed February 25, 2010.
- Prostate Cancer Foundation. Risk Factors. http://www.pcf.org/site/c.leJRIROrEpH/b.5802027/k.D271/Prostate_Cancer_Risk_Factors.htm Accessed February 16, 2010.
- ACS Detailed Guide: Prostate Cancer. How Is Prostate Cancer Staged? www.cancer.org. Accessed February 25, 2010.
- ACS Detailed Guide: How is Prostate Cancer Found? www.cancer.org. Accessed March 23, 2010.
- Prostate Cancer Basics. My Cleveland Clinic. http://myclevelandclinic.org/disorders/prostate_cancer/hic_prostate_cancer_basics.aspx. Accessed February 25, 2010.
- National Comprehensive Cancer Network. NCCN Treatment Summaries for People with Cancer. Prostate Cancer – Advanced. http://nccn.com/metastatic_prostate_cancer.aspx. Accessed February 18, 2010.
- Trelstar 3.75 mg, 11.25 mg, 22.5 mg [prescribing information]. Morristown, NJ: Watson Pharma, Inc.; 2010.
- ZERO The Project to End Prostate Cancer. http://zerocancer.org/site/PageServer?pagename=APC_Risk_Factors. Accessed February 16, 2010.
- National Comprehensive Cancer Network. NCCN Treatment Summaries for People with Cancer. Prostate Cancer–Localized. http://nccn.com/metastatic_prostate_cancer.aspx. Accessed February 24, 2010.
- Netter FH. Atlas of Human Anatomy. East Hanover, NJ: Novartis; 1997. Plate 338.
- ACS Detailed Guide: Prostate Cancer. How is Prostate Cancer Diagnosed? www.cancer.org. Accessed February 25, 2010.
- ACS Detailed Guide: Prostate Cancer. Expectant Management (watchful waiting) and active surveillance. www.cancer.org. Accessed February 25, 2010.
- ACS Detailed Guide: Prostate Cancer. Surgery. www.cancer.org. Accessed February 25, 2010.
- ACS Detailed Guide: How is Prostate Cancer Treated?. www.cancer.org. Accessed March 23, 2010
- ACS Detailed Guide: Prostate Cancer. Radiation Therapy. www.cancer.org. Accessed February 25, 2010.
- Firmagon full Prescribing Information. Ferring Pharmaceuticals. 2009.
- MedicineNet. Medical Dictionary. http://medterms.com. Accessed March 23, 2010.
- National Cancer Institute. U. S. National Institutes of Health. NCI Dictionary of Cancer Terms. http://cancer.gov/dictionary. Accessed March 25, 2010.
- The Free Dictionary. Medical Dictionary. http://thefreedictionary.com. Accessed March 23, 2010.
- Data on file. CSR DEB-TRI6M-301. Watson Pharma, Inc.
Trelstar® is indicated for the palliative treatment of advanced prostate cancer.
Important Safety Information
After your first injection of Trelstar®, you might feel a temporary increase in your cancer symptoms, such as pain in your bones, nerve disorder, blood in your urine, blockage in the canals leaving your bladder, or pressure in the spinal cord that may lead to weakness or paralysis with or without fatal complications. This is because the amount of testosterone in your bloodstream actually goes up for a short period after the injection. If your symptoms increase later than the first week or two following an injection, tell your doctor. The most common side effects that patients taking Trelstar® have are actually the effect of lowering testosterone levels. The most common effect of lowering testosterone is hot flushes or flashes. These are like the hot flashes women have around the time of menopause. Other side effects include bone pain, impotence (sexual side effect), tissue breakdown in the testicles, headache, leg pain, and swelling in the legs. Women who are or may become pregnant and those who are allergic to this type of drug should not take Trelstar®. A severe potentially fatal form of shock, hyper allergic response, and allergic swelling related to Trelstar® have been reported. For more information on these and other side effects, please talk to your doctor.