Hormonal therapy Hormones affect the growth of cells in your body, including cancer cells. Reducing hormone levels through hormonal therapy is a way of slowing and even stopping some cancers.
How does it work? Hormones are naturally occurring substances in your body that influence the growth and activity of your cells. One way to stop the spread of cancer cells is to reduce the number of hormones in the affected area. Hormonal therapy is commonly used to treat prostate cancer and some breast cancers.
Hormonal therapy and prostate cancer The male hormone testosterone supports the growth of prostate cancer. Reducing the levels of testosterone in the body can shrink or slow the growth of the cancer. It can also be used to inhibit the return of the cancer after successful treatment with radiotherapy or surgery.
If you need to reduce your testosterone levels urgently, you may be advised to have your testicles surgically removed (testicles are where your body produces testosterone). Otherwise, it’s likely you’ll receive hormone-reducing drugs.
The drugs that reduce testosterone production can be taken as pills or nasal sprays, or be injected under the skin. Sometimes the injections cause short-term irritation around the injection site, but the treatment itself is pain-free. You may be taking these drugs for a long time: it’s not unusual for hormonal therapy to go on for months or even years.
If you’re taking a drug that reduces testosterone levels, it’s possible that you’ll have erection difficulties. If you’re taking a drug that stops production of testosterone altogether, then erection difficulties are certain. Remember that once treatment is over, things may go back to normal; speak to your care team if you have any questions. Other side effects include hot flushes and sweats, tenderness around the breasts, fatigue, mood swings, weight gain and bone thinning.
Hormonal therapy and breast cancer The female hormones oestrogen and progesterone actually trigger the growth of some breast cancers. If you have one of those cancers, your care team may recommend hormonal therapy to reduce the levels of those hormones or block their effect.
Hormonal therapy is sometimes used before surgery to shrink a tumour, but with breast cancer it’s most commonly used after surgery to reduce the chance of the cancer returning.
The drug you’re prescribed may depend on whether or not you’ve been through menopause. In most cases, treatment goes on for many years. Sometimes, instead of hormone therapy, a care team will advise surgical removal of the ovaries where hormones are produced.
Side effects for hormonal therapy in women can include hot flushes and sweats, changes to menstrual periods, lowered sex drive, vaginal dryness or discharge, nausea, painful joints, fatigue and mood swings. Some women can experience long-term side effects including early menopause and bone thinning.
Things to ask
Why won’t it work for me? Hormonal therapy is effective on prostate cancer and some types of breast cancer, but not others. If your breast cancer is unlikely to respond to hormonal therapy then your care team may suggest chemotherapy to shrink a tumour before surgery or reduce the risk of a cancer returning after surgery.
Is it used for any other cancers? Hormones affect the growth of the cells in the lining of the womb. For that reason, hormonal therapy can also be an effective treatment for uterine cancer (also called womb cancer).
Words to know
Brachytherapy internal radiotherapy treatment that involves placing radioactive material in or near a tumour
Hormones naturally occurring substances that influence the growth of cells in your body
Lymphoma cancers of the lymphatic system
Myeloma cancer of the plasma cells found inside bone marrow
Stem cells early-stage blood cells found inside the bone marrow
Expert's insight: Keith Cox Hormonal therapy is often given over a period of months or sometimes years. Fortunately there are few side effects, particularly with some of the newer drugs, says Keith Cox, a nurse practitioner at Sydney Cancer Centre.
“Patients receiving hormonal therapy usually get fewer sider effects than patients who are having chemotherapy.
“Some patients who do experience side effects complain of weight gain and temperature changes, such as hot flushes and night sweats – a bit like early menopause. Some people go on alternative therapies to control this.
“The majority of the hormonal therapies are tablets but some are by injections – not into the vein, into the muscles. The injection doesn’t take very long at all, not even a minute. Depending on the drug, you might give that injection every month, or every three months. And that goes on until the therapy doesn’t work any longer.
“Some people might have mood changes with hormonal therapies, but it’s hard to say because we don’t see them that often if they’re taking their drugs as tablets. Only if they come into the clinic and report mood changes do we actually know about them.”
More help
Cancer Councils offer counselling, support networks, information and practical help. For details, call the Helpline or visit these websites.
JOHN STEAD John Stead was diagnosed with prostate cancer in 2003, on the day he turned 60. It wasn’t his ideal birthday present, but he steeled himself for the biggest battle of his life.
Four medical opinions later, John chose hormonal therapy in conjunction with external beam radiotherapy and a high dose of brachytherapy (a type of internal radiotherapy). The treatment was a success and although he needs to be checked every six months, John’s life is back to normal.
“Hormone treatment can be taken orally or through injections. The injections are generally done monthly or three-monthly, while the oral option is just a daily tablet. Some of the oncologists prefer injections as they say it stops the patient from cheating. When men get some of the side effects, the temptation’s there to stop the treatment.
“I took the treatment orally. For the first month, I felt ratty. I had hot flushes and, after a couple of months, I lost my erectile function. Don’t be surprised if you lose your libido, feel lethargic and have mood swings.
“I was in the shower one day and I felt a bit of a lump under my right nipple. A couple of days later the lump was on the other side as well. I started worrying about breast cancer. I went to see the doctor and he assured me my ‘man-boobs’ would go away once the treatment was done. It was just a side effect of the hormone treatment.
“The hot flushes settled down after a few months. You also have to force yourself to do exercise otherwise you’ll put on weight. In terms of the exercise and diet, you’ve got to be positive. There’s a tendency to wallow. There’s a lot more help in that area now.
“A recent study confirms that hormonal therapy prior to radiotherapy enhances the effect of the radiotherapy and shrinks cancer cells. I made the right decision to go through with it.”