When facing a diagnosis of prostate cancer, understanding your treatment options is crucial. Hormone therapy, a common approach in managing prostate cancer, can be a pivotal part of your journey towards health. In this article, we will delve into the specifics of hormone therapy and answer some common questions, ensuring you have the information needed to make informed decisions about your care.

Hormone therapy for prostate cancer works by preventing testosterone from reaching the prostate cancer cells, which usually need testosterone to grow.¹ It does this either by stopping testosterone from reaching the cancer cells or by stopping your body from producing testosterone at all.¹ Testosterone is a male hormone that controls characteristics, including sexual function and muscle strength.² Testosterone is not usually a problem, but for people with prostate cancer, it can accelerate the growth of cancer cells.² If testosterone is removed, the cancer will usually shrink, even if it has spread elsewhere.²

It is unlikely that hormone therapy alone will cure your prostate cancer, but it can control your cancer by delaying or managing any symptoms.¹ In people with more advanced or high-risk prostate cancer, hormone therapy is often combined with other types of treatment (e.g. radiotherapy or surgery) for added benefits.³

There are many different types of hormone therapy, some that have been around for a while and others that are fairly new. Though often effective, hormone therapy has a range of potential side effects. Read on to find out more about hormone therapy, including the different types, benefits, side effects, and other important considerations, like how to reduce the side effects of hormone therapy and how you will know if it is working.

Types of hormone therapy

Hormone therapy for prostate cancer can be administered in three main ways: surgery, tablets, or injections.⁴ The type of hormone therapy you have will depend on how advanced your cancer is, any other types of treatment you are receiving, as well as your preferences.⁴ It is also sometimes possible to have multiple types of hormone therapy at the same time.¹

Surgery

The main surgery used in hormone therapy is the removal of the testicles, known as an ‘orchidectomy.’⁵ Although this is a surgery, its main effect is as a form of hormone therapy, since the testicles are the main source of male hormones (such as testosterone).² As a result, orchidectomy surgeries cause most prostate cancers to stop growing or even shrink.²

Orchidectomy surgery is done as an outpatient procedure and is quite a simple process.⁵ Though all surgeries have risks, this surgery has a very low rate of complications and is usually very effective at lowering testosterone levels. The only very common short-term side-effect is swelling/bruising of the scrotum (the skin containing the testicles).⁴ However, the results of this surgery are permanent, and many people assigned male at birth (AMAB)  find the thought of removing their testicles upsetting.⁴ If looks are a concern, surgeons can insert artificial testicles that look very similar to normal ones into the scrotum, but for people AMAB  who have trouble accepting the removal of their testicles, there are several other treatment options.⁵

Tablets

The main form of hormone therapy given in the form of tablets is known as anti-androgens.⁶ Androgens are the name for male hormones like testosterone, and these tablets work by stopping testosterone from reaching the cancer cells.¹ Some common types of anti-androgen tablets are flutamide (Drogenil®), cyproterone acetate (Cyprostat®), and bicalutamide (Casodex®).⁴ Many could benefit from anti-androgens, but they will often be less effective than other types of hormone therapy for those with more advanced cancers.⁴ Like other forms of hormone therapy, they can be used on their own or with other treatments.³ On their own, anti-androgens are more likely to cause breast swelling and tenderness but are less likely to cause certain other side effects caused by hormone therapy, including sexual problems and bone thinning.⁴

There are also various newer types of hormone therapy given in the form of tablets, known as second-generation hormone therapy.⁷ They can either be used together with more traditional (‘first line’) hormone therapy or when your prostate cancer has stopped responding to the other types of hormone therapy.⁷ These include apalutamide (Erleada®), enzalutamide (Xtandi®), darolutamide (Nubega®), and abiraterone (Zytiga®).⁴ Apalutamide (Erleada®) is likely to be offered to people assigned male at birth (AMAB)  with locally advanced prostate cancer that has not yet spread to other parts of the body but has stopped responding to other types of hormone therapy.⁷ Enzalutamide (Xtandi®) and Abiraterone (Zytiga®) can be effective for prostate cancers that have spread to other parts of the body, either as an initial hormone therapy together with other treatments or when the cancer is no longer responding to other hormone therapies.⁴ Darolutamine (Nubega®) tablets are not intended to cure prostate cancer but can help keep it under control and delay the spread of prostate cancer to other parts of the body.⁷

Injections

Injections (or implants) work by blocking the messages from your brain that tell your testicles to produce testosterone.² They are as effective at lowering testosterone (and therefore controlling prostate cancer) as orchidectomy surgery to remove the testicles.⁵ Although injections and implants are both given using a needle, they work slightly differently. Injections inject the drug as a bit of liquid somewhere in your body depending on the type (usually under the skin or into a muscle), whereas implants put a small pellet under the skin in your belly, which slowly releases the drug.⁴ You will have injections or implants at your local hospital or GP surgery, and depending on the type you are having, you may have injections monthly or every three/six months.⁶

The most common type of injection/implant is called LHRH agonists, which include leuporelin acetate (Lutrate® or Prostap®), triptorelin (Gonapeptyl Depot® or Decapeptyl®), goserelin (Zoladex®) and buserelin acetate (Suprefact®).⁴ These all work in the same way. Although they are very effective at reducing testosterone in the longer term, LNRH agonists cause a short increase in testosterone levels soon after the first injection.¹ This can cause the cancer to grow quickly for a short period, which can make any symptoms you may have worse for a few days – known as a ‘tumour flare.^1,5 This flare can usually be avoided by taking anti-androgen tablets (discussed above) for a few weeks when starting LNRH agonist treatment.^2,5

A slightly less common type of injection/implant use is called GnRH antagonists (also called GnRH blockers), which describes degarelix (Firmagon®).⁴ Degarelix might be used as an initial treatment for prostate cancer that has spread to the bones.¹ It can help prevent cancer cells from growing around the spine and pressing on the spinal cord, which can be quite dangerous.^1,4 Usually, degarelix will be given as two injections on either side of your belly to start, and then a top-up injection every month.⁴ Degarelix does not cause a tumour flare, so there is no need to take anti-androgen tablets, and symptoms should start to improve almost instantly.¹ After the initial treatment, some men then choose to switch to an LHRH agonist.⁴

Benefits of hormone therapy

Hormone therapy is a very effective treatment to slow the growth of (or even shrink) prostate cancer, whether or not it has spread to other parts of your body.² It can improve your quality of life by reducing the symptoms of prostate cancer, especially more advanced symptoms like bone pain.² It can make other treatments like radiotherapy more effective when used together with them.¹

Side effects of hormone therapy

Hormone therapy, like all treatments, can cause numerous side effects. Most of these are because of reduced testosterone levels.³ All people AMAB are affected differently, and you may not get all (or even any) of the common side effects. If you are lucky enough not to get any side effects, this does not mean the treatment is not working.⁴ Side effects tend to last the length of the treatment (for orchidectomy surgery, it will be permanent) and sometimes persist for a short while after stopping, but men often find that they improve or become easier to manage over time.^5,6

Common side effects include:⁶

• Erection difficulties and reduced sex drive
• Hot flashes and sweats
• Mood changes
• Tiredness and difficulty sleeping
• Memory and concentration problems

Other side effects that may affect some people AMAB  on hormone therapy for extended periods (over 6 months) include:⁶

• Breast swelling or tiredness
• Weight gain and loss of muscle strength
• Bone thinning (osteoporosis)
• Increased risk of heart disease and diabetes

Reducing the side effects of hormone therapy

With the help of your doctor, many of the side effects of hormone therapy can be reduced using lifestyle changes and medications. The sexual side effects of hormone therapy can be challenging to manage, but drugs like sildenafil (Viagra) can help men achieve erections, although they do not help with the loss of sexual drive (libido) caused by low androgens.³ Hot flashes and sweats tend to improve as your body gets used to the treatment, but some medications can help if they are troublesome/persistent.⁶ Not smoking, eating well and keeping active has been shown to improve symptoms like tiredness, low mood, weight gain/muscle loss, and even reduce the risk of heart disease and diabetes.⁸ For those suffering from mood changes, therapy can often be helpful, whether officially through your doctor/counsellor or simply through a support system of family or friends.⁶ For people AMAB  worried about breast swelling, low-dose radiotherapy to the chest before treatment can prevent this, and other hormonal drugs like tamoxifen can be taken to reduce breast swelling during treatment.⁶ Finally, there are several drugs (most in a class of medicines called bisphosphonates) that can be used to slow or reverse the loss of bone mass/density for men on long-term hormone therapy.⁹

How can you know if the hormone therapy is working?

Your doctor will arrange regular appointments to monitor your treatment, including the effectiveness and any side effects.⁶ The effectiveness of the treatment is often tested using regular PSA blood tests, which check the levels of prostate-specific antigen (PSA) in your blood.⁴ PSA is a protein produced by prostate cancer cells (even those that they have spread to other parts of your body), so checking your levels of PSA is a useful way to monitor how well hormone therapy is working for you.⁴

Summary

This article has discussed the role of hormone therapy in the management of prostate cancer. We have seen that hormone therapy works by preventing testosterone (which prostate cancer needs to grow) from reaching prostate cancer cells. Whilst hormone therapy is unlikely to cure prostate cancer on its own, it can be effective in helping to control it. The article outlines the three main forms of hormone therapy: surgery (orchidectomy), tablets (anti-androgens and second-generation hormone therapy), and injections/implants (LNRH agonists and GNRH antagonists). Each type has benefits and potential side effects, which this article has outlined. We have also seen that many of the side effects can be well-managed with medications and lifestyle changes and should be monitored through regular appointments alongside PSA blood tests to check the effectiveness of treatment.