What is hormonal therapy?
Hormonal therapy is a treatment option for locally-advanced prostate cancer. It aims to stop the growth of the tumour.
The growth of prostate cancer cells is dependent on male sex hormones called androgens. Testosterone is the most important androgen. Androgens are mainly produced in the testicles. Hormonal therapy either stops the production or blocks the action of androgens. This is known as castration.
Another name for hormonal therapy is androgen deprivation therapy (ADT). It can be performed surgically or with drug treatment. In surgical therapy, both testicles are removed in a procedure called bilateral orchiectomy. The surgery is generally done under local anaesthesia. Drug therapy to stop the production of androgens includes LHRH agonists and LHRH antagonists. These drugs are available as depot injections right under the skin or into the muscle. Anti-androgens are drugs that block the action of androgens. They come as a pill. All of these therapies cause castration.
Castration has physical and emotional consequences. The most common are hot flushes, lower sex drive, and erectile dysfunction. The effects of surgical castration are permanent. In chemical castration, some of the symptoms may disappear after the treatment. Do not hesitate to discuss any concerns with your doctor.
In locally-advanced prostate cancer the standard treatment to cure the disease is hormonal therapy in combination with radiation therapy.
What are the side effects of hormonal therapy?
Hormonal therapy stops the production or blocks the action of male hormones, and causes castration. Your body can react to castration in different ways. The most common side effects of castration are:
- Hot flushes
- Lower sex drive
- Erectile dysfunction
- Increased risk of heart disease
- You could also experience pain, for example in your joints, your back, your bones, or muscles.
Changing hormone levels can affect your blood and cause high blood pressure, dizziness, and bruising. You may also be at higher risk of infection, especially in the nose or throat, or urinary tract infections.
Loss of appetite and weight loss can also be a result of castration. These may be related to diarrhoea, constipation or vomiting caused by the hormone changes.
Other side effects may include coughing, shortness of breath, headaches, and peripheral oedema.
The different treatments may cause side effects as well. LHRH antagonists may cause an allergic reaction. Anti-androgens may cause swelling of your breasts. This is called gynecomastia and can be painful in some cases. To prevent gynecomastia your doctor may recommend radiation therapy of your chest before the start of the hormonal therapy. In rare cases, you may need surgery to remove the mammary glands. Anti-androgens could worsen hot flushes. These can be treated with low-dose oestrogen therapy. Oestrogens can increase the risk of heart disease. Flutamide can cause diarrhoea.
How bothersome the side effects of hormonal therapy are, and when they appear, varies from person to person. This is related to your general health and the type of treatment you get.
With time, prostate cancer cells become resistant to hormonal therapy, and the cancer will start to grow again. This is known as castration-resistant prostate cancer. How long this takes to develop varies from person to person.
If during follow-up the prostate-specific antigen (PSA) level shows that the prostate cancer has not been completely removed you may need additional treatment to remove all tumour cells. Common treatment options are:
- New hormonal agents
It is generally recommended to visit your doctor every 3 months after you start hormonal therapy, to monitor the disease. Each visit includes a physical examination and a PSA test. These tests are used to see how you are responding to the treatment. During these visits you can discuss with your doctor if there is a treatment option to manage side effects. Your doctor will adjust the follow-up visits according to your needs.