Hormonal therapy is a systemic rather than a local therapy; in other words, it treats the whole body rather than a particular area. For this reason, hormonal therapy is most often prescribed to treat prostate cancer that has spread outside the prostate gland (Stages N1 or M1), to treat a recurrence of prostate cancer after another therapy has been used (e.g., external beam radiation), or to treat men who are at a high risk of experiencing a recurrence after surgery or radiation therapy. Hormone therapy works be depriving prostate cancer cells of the male hormones (androgens) that they need to grow and flourish. This androgen deprivation can be accomplished surgically, through the removal of the testicles, or by using medication that prevents the production of androgens or blocks their effect on prostate cells. THE SURGICAL OPTION Orchiectomy or surgical castration is the removal of the testicles to prevent the production of testosterone, the principle male hormone or androgen. The goal is to deprive cancer cells of testosterone thereby causing the prostate cancer to shrink or at least preventing its growth. Few men today decide on this treatment, choosing drug-based hormonal therapy instead, possibly because the effects of drug-based hormonal therapy are reversible. However, this surgery is relatively simple and has other advantages. It is over quickly and usually causes less long-term inconvenience and expense than taking medication to stop androgen production or block its effects. THE MEDICAL OPTION Two main sorts of drugs are used to treat prostate cancer hormonally. One sort, called luteinizing hormone-releasing hormone (LHRH) analogues, interferes with the production of androgens. The other sort, called antiandrogens, blocks the effects of various male hormones on the cells of the prostate. These drugs are used at various times during the treatment of prostate cancer, and they are used in combination or individually. LHRH Analogue Therapy In this therapy, you receive regular doses of luteinizing hormone-releasing hormone analogues. Initially, these LHRH analogues stimulate androgen production, but, in about two weeks, the level of testosterone falls dramatically and extremely low levels can be maintained as long as the drug is continued. LHRH analogue therapy is usually administered by injection every 2 to 4 months or monthly. Injections are into the muscle or under the skin. In Canada, the most used LHRH analogues are goserelin (Zoladex® ), leuprolide (Lupron® or Eligard® ), and buserelin (Suprefact® ). Advantages of LHRH analogue therapy include the simplicity of the treatment, its relative safety, and the avoidance of an irreversible surgical castration while achieving castration levels of androgens. Disadvantages include the inconvenience and responsibility of visiting your physician regularly and following medication schedules, the possibility that the initial increase in testosterone levels (testosterone surge) may cause a worsening of cancer symptoms (flare), and the general side effects of hormone therapy. (See side effects below.) Cost is another disadvantage, although, in Canada, health insurance usually covers these drugs for men over 65. Antiandrogen Therapy Antiandrogens are drugs that block the effects of some forms of testosterone on the cells of the prostate. They work by preventing male hormones from attaching to the androgen receptors of the prostate cells, so they are sometimes called androgen blockers. There are two types: steroidal antiandrogens and non-steroidal antiandrogens. Steroidal antiandrogens include megestrol acetate (Megace® ) and cyproterone acetate (Androcur® ). These act like female sex hormones and resemble progesterone in structure. Both can lower levels of LH temporarily as well as block the effects of androgen. These anti-androgens are usually taken orally on a daily basis and may be given with low doses of estrogen, another female hormone. Non-steroidal antiandrogens include flutamide (Euflex® ), bicalutamide (Casodex® ), and nilutamide (Anandron® ). These are most commonly used in combination with LHRH analogues either to neutralize the flare effect of this treatment or to block androgens unaffected by LHRH analogue therapy or orchiectomy. Some male hormones are produced outside of the testicles (in the adrenal glands, for example), and LHRH analogue therapy cannot eliminate them. Consequently, non-steroidal antiandrogens are sometimes used with LHRH analogues in combination therapy to attempt to achieve what is variously known as maximal androgen deprivation (MAD), maximum androgen blockade (MAB), or total or complete androgen blockade (TAB and CAB respectively). BENEFITS, DISADVANTAGES, AND SIDE EFFECTS These vary and depend on the form of hormonal treatment used and on the specifics of each man's disease, general health, and treatment regimen. Benefits
Hormone therapy may slow the growth of prostate cancer; some men's lives can be prolonged for 10 to 15 years while others experience relief from the symptoms of their disease for only a year or less.
This treatment is one of the best available for decreasing the complications and pain experienced by men with metastatic prostate cancer.
Hormone therapy drugs are readily available from medical professionals and easily administered either through injection or pills.
Surgical castration is a fairly simple operation that has been performed for many years.
The side effects of androgen deprivation are usually relatively modest when compared with the effects of prostate cancer and can often be managed or treated.
Disadvantages
The main disadvantage is that hormone therapy does not cure prostate cancer.
The treatments only work for a certain amount of time until prostate cancer cells become hormone resistant or hormone refractory.
Men must follow ongoing treatment regimens.
Side Effects The side effects of hormone therapy relate to androgen deprivation, in other words, to drastically reducing male sex hormones in a man's body. These side effects vary widely and depend on the drug being used, the treatment regimen, and each man's individual situation and general health. As hormonal therapy is often used in combination with other treatments or before or after other treatments, it is also sometimes difficult to determine what percentage of men will likely suffer which side effects and in what circumstances.
Men may experience sweating, hot flashes, and swelling or tenderness of the breasts.
A decreased sex drive (libido) and the eventual loss of erections (erectile dysfunction) are frequently side effects.
Some men experience a lack of energy, anaemia, mood swings, or depression.
Over the long term, hormone therapy can cause a loss of bone density and of muscle strength.
THE VARIOUS USES OF HORMONE THERAPY Hormone therapy is used at various times and in various ways to treat prostate cancer, and new drugs and treatment regimens are being tested all the time. Let's examine a few of the most common ways hormone therapy is used. Combination Hormone Therapy As mentioned, some research suggests that combining the use of antiandrogens with either LHRH analogue therapy or orchiectomy is more effective than either of these treatments alone. Medical professionals remain uncertain, however, about whether the possible (and often modest) benefits of this approach outweigh the risk of increased side effects. Intermittent Hormone Therapy Because men diagnosed with recurring prostate cancer and placed on hormone therapy are living longer that ever before, the side effects they experience from being so long without significant levels of male hormone can affect the quality of their lives. Intermittent hormone therapy is an "experimental" treatment regimen that seeks to limit the side effects of hormone therapy while maintaining its efficacy. Here is what it usually entails. Once a man on hormone therapy is without symptoms and his PSA level has been lowered and stabilized, he is taken off hormone therapy medication until his PSA level increases (usually to about 10). At that point, hormone therapy resumes. Usually, men are treated for eight months, and, obviously, time off treatment varies. After hormone drugs are stopped, most men recover their normal testosterone levels in about 4 months and see their energy and sex drive improve. Note that the long-term outcome of intermittent hormone therapy on survival is not yet known. Neoadjuvant Hormone Therapy Sometimes, hormone therapy for prostate cancer is given before a local treatment, such as radiation. This is called neoadjuvant hormone therapy. Often, its purpose is to reduce the size of the tumour to make the "main" treatment potentially more effective or possible. Currently, research does not support the use of neoadjuvant hormone therapy before a radical prostatectomy. However, patients receiving external beam radiation are often treated with neoadjuvant hormone therapy (for 3 months) and with adjuvant hormone therapy (for 2 or more years). Adjuvant Hormone Therapy Sometimes, hormone therapy is used directly after surgery or radiation to treat any microscopic cancerous cells that may remain in the body. Doctors often use the term minimal residual disease (MRD) to refer to these isolated or disseminated cancer cells. Various studies confirm that adjuvant hormonal therapy can prolong survival for men with locally advanced prostate cancer (prostate cancer that extends beyond the prostate gland but shows no evidence of lymph node or distant metastases). Research is currently examining the best time to begin hormone therapy for patients whose prostate cancer has spread to the lymph nodes or is locally advanced and whose main treatment is surgery or radiation. Most physicians currently delay adjuvant hormone therapy until PSA levels begin to rise rapidly or are greater than 6 to 10. However, some recent research indicates that an earlier start may be better for long-term survival among some categories of patient. HORMONE RESISTANT OR HORMONE REFRACTORY PROSTATE CANCER Put simply, prostate cancer is called hormone resistant or hormone refractory when it continues to grow in spite of being deprived of male hormones. Sometimes, these two terms are used interchangeably, and sometimes hormone resistant prostate cancer is defined as prostate cancer that may respond to a change in hormonal therapy while hormone refractory prostate cancer is defined as cancer that progresses in spite of any hormone therapy treatment regimen. When a man's cancer stops responding to hormone therapy, his PSA level rises, his cancer grows, and his life is threatened. In this circumstance, chemotherapy or palliative treatments are usually recommended. For more information: Network News special issue on hormone resistant prostate cancer, January 2009 Another step in a new direction: PROVENGE® approved by FDA, May 2010 Battling hormone resistant prostate cancer (ZD4054 and Provenge), July 2007 Taxotere ® : Encouraging news for men with metastatic prostate cancer, December 2005 A ray of hope for men with hormone refractory prostate cancer, August 2004
To find a local support group, move your pointer over the “Support Group” button and then over “Find a Group Near You,” and click on the appropriate Canadian region.
Treatment Options: