Brachytherapy for early prostate cancer

Radiation can be given to treat early prostate cancer. Radiation can be given internally or externally. When radiotherapy is given internally, it is called brachytherapy. Research shows that brachytherapy is just as good as surgery or external beam radiotherapy at treating certain prostate cancers. The doctor who specialises in giving radiotherapy is called a radiation oncologist.

Brachytherapy is a way of giving radiation directly into your prostate gland. The radiation destroys your prostate cancer. The treatment is usually used on its own, but if there is a higher chance of the cancer spreading, it can be used together with external beam radiotherapy and hormone therapy. In permanent seed brachytherapy, the radiation comes from small radioactive seeds put into your prostate.

The radiation is released slowly over a number of months. The seeds are not taken out but the radiation fades away over time.

It is a safe therapy with no risk to other people. The aim of brachytherapy is to fully get rid of your prostate cancer.

Who is suitable for permanent seed brachytherapy?

Not all men are suitable for permanent seed brachytherapy. It will depend on the stage and grade of your prostate cancer and the size of your prostate gland. You may not be suitable if you have trouble passing urine, have a very large prostate gland or have recently had a resection of your prostate gland.

Your doctor will let you know if you are suitable for brachytherapy or not. If you have a larger prostate gland, you may be given hormone therapy to shrink it before brachytherapy.

If you have higher-risk prostate cancer, you may receive permanent seed brachytherapy along with another treatment; for example, you may need hormone therapy as well.

In a small number of situations you may be offered a different type of brachytherapy using a temporary source of radiation called (HDR) brachytherapy.

(HDR) brachytherapy uses a high-dose rate of radiation, instead of using permanent seeds a temporary source of radiation is inserted into the prostate gland for a few minutes.

This is usually combined with external beam radiation and/or hormonal therapy. (HDR) brachytherapy is not widely available in Ireland at present.

Your doctor will discuss with you if brachytherapy is a suitable treatment option for you and whether they recommend it on its own or in combination with some of the other treatments. Each situation is decided upon individually and is influenced by many factors. Each treatment plan is tailored to what is felt to be the most appropriate one for you. 

What happens before treatment with permanent seed brachytherapy can be given?

An ultrasound scan of your prostate is done first. This can happen some weeks or days before the seeds are put in or on the same day. The scan lasts about 15 minutes. It uses ultrasound waves to find out the exact size and shape of your prostate gland so your doctor can work out how many seeds need to be put in.

Your nurse will let you know if your bowels need to be empty for the test. You may also have uro-flow studies done to measure the flow strength of the urinary stream as you pass water.

How are the seeds put in?

You may be asked to follow a special diet the day before the seeds are put in (implanted), and have an enema (a fluid solution gently put in in through your back passage) which then causes you to clear your bowels on the morning of the procedure and, or the evening before. The hospital staff will explain this to you beforehand.

You will be given advice on any medication to avoid beforehand as well. You will be taken to an operating theatre to have the seeds put in under a general or spinal anaesthetic. It takes about 90 minutes to put in all the seeds.

An ultrasound probe is first put in your back passage to show up your prostate. Then around 60 to 120 radioactive seeds are preloaded into needles which are put in through the skin between your prostate and your anus (back passage). The seeds are then guided into your prostate gland. You will not have a surgical incision (cut).

Some swelling of your prostate may happen, so a tube (catheter) is put into your bladder to drain any urine while you are having the procedure. It may be left in for a couple of hours or overnight and you must be able to pass urine normally before you go home.

Before going home you may be given a prescription for antibiotics, pain killers and alpha blockers (tablets to help relax the bladder and improve the flow strength as you pass urine) to take for a directed length of time afterwards. Speak with your prostate nurse to get further advice before going home.

How safe is the radiation?

The seeds do carry a small risk to health. It is safe for you to be around other people and pets during this time. The radiation released by the seeds targets the prostate gland only. But as a precaution it is best to avoid close physical contact (less than arm’s length) with small children or pregnant women for the first two months after treatment. This means not allowing small children on your lap for more than a few minutes.

Your doctor or nurse will give you more detailed information about this beforehand. You might be asked to strain your urine for the first weeks after treatment.  It is possible but not that common that you may pass a seed when passing urine. The radiotherapy unit will give you instructions if this happens so it is important to let them know. Do not handle the seed directly with you fingers.

If you need to go into hospital and have an operation for another reason during the first year after treatment, it is best to speak to your radiotherapy unit about the risk of exposure from the radiation.

How long do the seeds remain in place?

Most of the radiation is released into your prostate gland over the first 3 months. This radiation is then absorbed within your prostate. After about 12 months, the seeds are no longer active and can stay in your prostate without doing any harm.The radiotherapy unit may give you a medical alert card detailing the treatment you have had. This is to alert other medical professionals in the event of you having a medical emergency.It will direct the staff to contact your radiotherapy unit for specific advice. It is important to carry this with you at all times for the duration of time recommended by the unit. This card is also necessary for airline travel, as some of the security sensors may be triggered by the weak radiation emitted from the seeds.

What about sex after brachytherapy?

It is safe for you and your partner to sleep in the same bed (provided your partner is not pregnant) . Talk to your medical team for further advice. It is not unusual for some men not to feel like having sex in the first few weeks after treatment. 

This can often be due to tiredness or local side-effects like pain or swelling around the area of the prostate. These symptoms normally ease with time. There is a small risk that a seed may pass with the ejaculate fluid / semen when you are having sex. 

As a precaution you should use a condom for the first eight weeks after treatment. Don’t worry if your semen is black or brown in colour. This is normal and due to bleeding when the seeds are put in. You can talk to your doctor or nurse about when you can resume sex after brachytherapy. They can give you an advice sheet about this.

Advantages of brachytherapy

  • Treatment time is short, taking 1-2 days

  • You can return to your normal daily routines quite quickly

  • Compared to external radiotherapy, brachytherapy may have fewer immediate side effects and cause less damage to surrounding tissues like the back passage, urethra and bladder

Disadvantages of brachytherapy:

  • Usually not recommended to have surgery after brachytherapy if further treatment was necessary

  • It can cause urinary and errection or bowel problems

  • Discomfort after the implant has been done in the short term

What are the side-effects of brachytherapy?

It is common to feel mild soreness and some bruising between your legs for a few days after the seeds have been put in. Your doctor can prescribe mild painkillers to relieve this. You may see some blood in your urine afterwards but most bleeding usually goes within 48 hours. If it goes on beyond that, let your doctor know. To help prevent blood clots and flush out your bladder, drink plenty of fluids (about 1½ to 2 litres a day).

It may take a few days before you experience any side-effects. Usually they are at their worst a few weeks after the seeds have been put in. You may get some or all of the side-effects. Each man experiences them differently, so it is hard to know exactly how you will feel.

Side-effects may include:

  • Urinary Problems

  • Erectile Dysfunction

  • Bowel problems

  • Fatigue

  • Infertility

Urinary problems

The radiation can cause inflammation of your urethra. This is the tube through which you pass urine. The radiation might also irritate your bladder.

This can cause symptoms such as burning when you pass urine, needing to pass urine more often, having a slow stream, finding it harder to start passing urine, and needing to go more quickly than you used to. If you cannot pass urine afterwards, this is called urinary retention.

This does not happen very often but if it does, you will need to have a tube (catheter) put in for a time.

Urinary side-effects get worse in the first few weeks after treatment. They usually improve over time as the seeds lose some of their radiation. The urinary side-effects may mean that you need to go to the toilet very often, day and night. This can interfere with your normal daily activities for a while.

If your sleep is disturbed by having to get up several times during the night, it can make you feel quite tired. 

Drinking plenty of fluids and avoiding drinks with alcohol or caffeine, such as tea, coffee and cola, may ease these problems. It helps to drink 1½ to 2 litres a day.

You might also need tablets to help these side-effects for a time. These tablets are called alpha blockers they may help to relax the muscle within the prostate and to reduce the narrowing of the water tube which runs through the centre of the prostate.

If you have urinary symptoms before brachytherapy, you are at a higher risk of having problems passing urine after the treatment. Urinary incontinence is rare after brachytherapy. If you have had surgery to your prostate gland before brachytherapy, you will have a higher risk of incontinence.

If you would like to read further information, you can visit our section Urinary symptoms, catheters and prostate cancer treatment.

If you would like to receive a print copy of this free factsheet call us on the Cancer Nurseline freephone 1800 200 700 between 9am and 6pm Mon-Thurs and between 9am and 5pm on Friday. If you prefer, you can also visit a Daffodil Centre if one is located in your hospital. Find your nearest Daffodil Centre here.  

Erectile dysfunction

Brachytherapy can cause damage to the nerves and blood vessels near your prostate gland. This means that you might be unable to get normal erections after the treatment. This is called erectile dysfunction, or impotence.

You may not notice it until years after your treatment. It may also become a long-term problem and be permanent. Remember- 2 years after brachytherapy around 2 out of 10 men have erectile dysfunction; 3 years after brachytherapy 5 out of 10 men may have it.

Your risk of erectile dysfunction will increase if you have had erection problems before your treatment. If you have hormone therapy and external beam radiotherapy together with your brachytherapy, you are at a higher risk of erectile dysfunction than those men who have brachytherapy alone.

You may find this side-effect of treatment very hard to deal with. Naturally, it can affect your relationship with your partner and your sex life. Do not feel embarrassed to talk to your doctor or nurse about this problem. There are practical ways and several treatments available to help overcome it.

For further information please visit our section on sex, erectile dysfunction  and prostate cancer. You can call the Cancer Nurseline on free phone 1800 200 700 if you would like a copy to be posted or if you wish to speak confidentially with a specialist nurse. If you prefer, you can also visit a Daffodil Centre if one is located in your hospital. Find your nearest Daffodil Centre here

You can also read further information about sex and prostate cancer here.

Bowel problems

You may get inflammation of your bowel after brachytherapy. This may cause some bleeding or a change in your bowel habits, such as needing to go to the toilet more often. This side-effect can appear straight away or up to 2 to 3 years after your treatment.

If this happens, talk to your doctor, as there may be treatments that can help. You will be given advice on what to do if this happens to you. It is important that any doctor who treats you for bowel problems after brachytherapy is aware that you have had brachytherapy. If you are unsure then contact the radiotherapy unit for advice.

For advice on eating, call us on the Cancer Nurseline on 1800 200 700 and ask for a free print copy of the booklet Diet and Cancer

You could also visit a Daffodil Centre if one is located in the hospital you are attending. Find your nearest Daffodil Centre here


You may experience tiredness from the radiation or from getting up a lot at night to pass urine. It usually takes a few months after treatment for this to improve.

Call the Cancer Nurseline on 1800 200 700 for a free copy of the booklet called Coping with Fatigue .You can also download the Coping with Fatigue booklet here or pick one up at the Daffodil Centre if there is one located in your hospital. Find your nearest Daffodil Centre here.


Brachytherapy for prostate cancer may affect your fertility. This means you might be unable to father a child in the future. If this is important to you, talk to your doctor about this effect before your treatment.

If you have a partner, you may find it helpful to see the doctor together so that you can both talk about your concerns. If your sperm count is normal, it may be possible to store your sperm before radiotherapy for later use. Remember it is not safe to assume you are sterile after radiotherapy.

Side-effects in general

If you would like more information on brachytherapy, call the Cancer Nurseline on 1800 200 700 for a free copy of the booklet Understanding Radiotherapy or visit a Daffodil Centre if there is one in the hospital you visit. You can also download the booklet Understanding Radiotherapy.

You might also like to view our section on radiotherapy for further information and view a film about radiotherapy. 

What follow-up will I need?

You will be given a follow-up appointment to see the radiotherapist. This usually happens four to six weeks after your brachytherapy. This is a time to check the positioning of the seeds with a CT scan and for you to talk about any side-effects that may be bothering you.

You can also expect to have a PSA blood test done regularly to check that the brachytherapy has worked. Follow-up will vary between hospitals - your doctor or nurse will be able to tell you how often you will need a PSA blood test done.

If the brachytherapy has been successful you would expect the PSA level to drop, though how quickly it falls can vary from one man to another. Your PSA may rise again after brachytherapy as some prostate cells may still produce PSA. Sometimes the PSA level may rise and fall one to two years after treatment and this is called a PSA bounce. It is not necessarily a sign that the cancer has come back. The PSA should drop to its lowest level after 18 months to 2 years. This is often called the PSA nadir.

Where is brachytherapy available in Ireland?

Public hospitals:

Private hospitals:

Note: There are links to external websites on this page. The Irish Cancer Society is not responsible for the contents of external websites

Date Last Reviewed: 
Monday, July 28, 2014
Date Last Revised: 
Monday, May 18, 2015