Prostate cancer cells usually need testosterone to grow. Hormone therapy, also called androgen deprivation therapy or ADT, lowers testosterone or blocks its effects. It does not usually cure prostate cancer on its own, but it can shrink tumours, slow their growth and make other treatments work better.
How ADT works
Most testosterone is made in the testicles, under the control of signals from the brain. ADT interrupts this process. The main types are:
- LHRH agonists: injections or implants, such as goserelin or leuprorelin, that switch off the signals telling the testicles to make testosterone. They can cause a brief rise in testosterone at first, so a short course of tablets is often given at the start.
- GnRH antagonists: injections or tablets, such as degarelix or relugolix, that lower testosterone quickly without an initial rise.
- Anti-androgens: tablets, such as bicalutamide, that block testosterone from reaching cancer cells.
- Newer hormone treatments: such as abiraterone, enzalutamide, apalutamide and darolutamide, used in more advanced or high-risk disease.
Surgical removal of the testicles, called orchidectomy, is another option but is rarely used now.
When ADT is used
ADT may be recommended:
- with radiotherapy, for intermediate or high-risk localised cancer, for a period before, during and after
- for locally advanced cancer, alongside radiotherapy
- when cancer has spread beyond the prostate
- when PSA rises after previous treatment
It is not usually given alongside surgery for localised cancer. Our guide to surgery or radiotherapy explains how the main treatments compare.
How long it lasts
The length of treatment varies. With radiotherapy, it may be given for six months to three years. For advanced cancer, it is often continued long term. Some men have intermittent therapy, with planned breaks when PSA is low. During breaks, testosterone can recover and side effects may ease.
Common side effects and how to manage them
Hot flushes: the most common side effect. Wearing layers, avoiding triggers such as hot drinks and alcohol and keeping a fan nearby can help. Medicines are available if flushes are severe.
Tiredness: regular exercise, even brisk walking, is one of the most effective ways to reduce fatigue.
Reduced sex drive and erection problems: common while testosterone is low. Talk to your team about support.
Weight gain and muscle loss: strength exercises and a balanced diet help.
Bone thinning: long-term ADT can weaken bones. Your team may check bone density, recommend calcium and vitamin D and suggest weight-bearing exercise.
Mood changes: some men feel low, irritable or emotional. Our article on mental health and prostate cancer discusses support.
Heart and metabolic effects: ADT can raise blood sugar and cholesterol. Regular checks with your GP are recommended.
Breast tenderness: more common with anti-androgen tablets.
The importance of exercise
Research consistently shows that regular exercise helps men on ADT to manage tiredness, maintain muscle and bone strength, control weight and improve mood. A mix of aerobic exercise and resistance training is ideal. Prostate Cancer UK has practical exercise guides.
Monitoring during treatment
You will have regular PSA tests to check how well treatment is working. Our guide to PSA after treatment explains how levels are interpreted. Blood tests may also check testosterone, blood sugar and cholesterol.
Questions to ask
- Why is hormone therapy recommended for me?
- How long will I need it?
- What side effects are most likely?
- What can I do to reduce them?
- How will we know it is working?
NICE guidance on prostate cancer sets out when ADT should be offered. Our prostate cancer page explains the treatments in context.
Professor Prokar Dasgupta can explain where hormone therapy fits in your treatment plan at The London Clinic. Please contact the clinic to arrange a consultation.