Homonal therapy

What is hormonal therapy?

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.

Bilateral orchiectomy

Bilateral orchiectomy, or surgical castration, is a surgery to remove both testicles and aims to stop the production of androgens. The surgery can be done under local anaesthesia. If you have a history of cardiovascular disease, your doctor may advise you to see a cardiologist before starting with hormonal drug therapy.

Read more about bilateral orchiectomy

How is bilateral orchiectomy performed?
During surgery, you will lie on your back. You generally receive local or spinal anaesthesia. In some cases your doctor may recommend general anaesthesia. The surgeon makes an incision in the scrotum to remove both testicles. Because the tissue that surrounds the testicles is not removed, the scrotum will not look totally empty.

How do I prepare for the procedure?
Your doctor will advise you in detail about how to prepare for the procedure. If you need general anaesthesia, you must not eat, drink, or smoke at least for 6 hours before surgery. If you are taking any prescribed medication, discuss it with your doctor. You may need to stop taking it several days before surgery. Your doctor will advise you on when you can start taking it again.

Bilateral orchiectomy is a treatment option in:

  • Localised prostate cancer
  • Locally advanced prostate cancer
  • Metastatic prostate cancer

Chemical castration

If you prefer not to undergo surgical hormonal therapy, there are drugs which can stop the production of androgens. The most common drugs are LHRH agonists and LHRH antagonists. The aim of these drugs is to stop the growth of the tumour by chemical castration. How they do this varies for each group of drugs. Each drug is different in how it is applied. If you have a history of cardiovascular disease, your doctor will advise you to see a cardiologist before starting with hormonal drug therapy.

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. To delay castration resistance, your doctor may recommend to pause the hormonal drug therapy. This is called intermittent hormonal therapy.


Read more about chemical castration

LHRH agonists
LHRH agonists stop testosterone production in the testicles. They are administered as a depot injection right under the skin or into the muscle. These injections can last for 1, 3, 6 or 12 months. Discuss with your doctor which option is best for you.

In the first days after the first injection, LHRH agonists increase your testosterone level before they decrease it. This is known as a flare. The increase in testosterone level can cause the tumour to swell. In rare cases this could be dangerous and can cause difficulties urinating. Your doctor might give you a low dose of anti-androgen drugs to prevent damage from rising testosterone levels.

LHRH antagonists
LHRH antagonists are a new form of hormonal drug therapy. They do not need to be combined with an anti-androgen for the first weeks because they do not cause a flare. Degarelix is the most commonly used LHRH antagonist. It needs to be administered every month by injection under the skin.

Anti-androgens block the action of testosterone. As a result, the tumour will grow slower or stop growing completely. The most commonly used anti-androgens are cyproterone acetate, flutamide, and bicalutamide. They all come as a pill, and are taken every day.

Cyproterone acetate is usually administered in two or three daily dosages. Flutamide is administered three times a day. Bicalutamide is the most common antiandrogen, and it is taken once a day.

Chemical castration is a treatment option in:

  • Locally-advanced prostate cancer
  • Metastatic prostate cancer
  • Castration resistant prostate cancer

New hormonal agents

Abiraterone acetate

The body needs an enzyme called CYP17 (17α-hydroxylase) to produce testosterone. CYP17 is found in the testiclesadrenal glands, and prostate cancer cells. The new hormonal agent abiraterone acetate blocks CYP17 so that no testosterone is produced.

Abiraterone acetate is taken twice a day as a tablet, and always used in combination with the steroid drug prednisone. Discuss with your doctor if abiraterone acetate is an option for you.


Prostate tumours need androgen receptors to grow. Enzalutamide is a new hormonal agent that blocks androgen receptors. It aims to lower the level of PSA in the blood and slow down the growth of the tumour. Unlike abiraterone acetate, you do not need to take additional steroids while taking enzalutamide.

Abiraterone acetate is taken twice a day as a tablet, and always used in combination with the steroid drug prednisone. Discuss with your doctor if abiraterone acetate is an option for you.

New hormonal agents enzalutamide and abiraterone acetate are a treatment option in:

  • Castration resistant prostate cancer

Side effects

What are the side effects of bilateral orchiectomy?

Complications after a bilateral orchiectomy are rare and include pain around the scrotum, bleeding, infection, or delayed healing of the wound. In most cases, the way the scrotum looks will not be affected by the surgery.

Recommendations for 2-3 weeks after the surgery:

Avoid heavy exercise
Avoid hot baths
Avoid the sauna
You have to see your doctor or go back to the hospital if you:

Develop a fever
Have severe pain
Notice that the wound starts to bleed or leak a transparent fluid
Bilateral orchiectomy results in permanent castration. This has physical and emotional consequences. Do not hesitate to discuss any concerns with your doctor. Together you can decide if other treatment options are more suitable for you.

What are the side effects of chemical castration?

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 gynaecomastia and can be painful in some cases. To prevent gynaecomastia 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 oestrogens. 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.

What are the side effects of new hormonal agents: abiraterone acetate and enzalutamide?

Abiraterone acetate
The most common side effects of abiraterone acetate include fatigue, lower levels of potassium in the blood, high blood pressure, swelling or discomfort of the joints, and swelling caused by fluid retention.

While taking abiraterone acetate you may become tired and feel out of breath because of lower levels of red blood cells. Other changes to the blood may cause a fast, pounding, or irregular heartbeat, increased thirst and loss of appetite, nausea or vomiting, or fast weight gain.

The most common side effects of enzalutamide are a feeling of weakness, back pain, and fatigue.

Read more about how to deal with the side effects of hormonal therapy in the section Coping with cancer.

Follow up

What will the follow-up be like?

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.

In need of support?

The European Prostate Cancer Coalition is a global collaboration of patient organisations dedicated to prostate cancer patients.