Permanent seed brachytherapy for prostate cancer

Permanent seed brachytherapy (pronounced brack-ee-therapy) is when your doctor puts very small radioactive metal seeds into your prostate gland. The seeds slowly release a low level of radiation into the area of the prostate over a few months. It is a type of internal radiotherapy.

With brachytherapy, your doctor puts the radioactive source or seeds as close to the cancer as possible. So that the cancer gets a high dose but nearby tissues and further away the levels of radiation are low. 

Permanent seed brachytherapy is also called permanent brachytherapy or low dose rate (LDR) radiotherapy. 

When you might have permanent seed brachytherapy

Permanent seed brachytherapy is a treatment for early stage prostate cancer. This means the cancer hasn't spread outside of the prostate.

If your prostate gland is too big you might need hormone therapy for 3 months before the radiotherapy treatment. The hormone therapy shrinks the prostate and makes it easier to put the seeds into the right place.

How many hospital appointments you might have

You might have the treatment during 1 or 2 stages. This depends on what is available at your hospital. 

1 stage procedure 

If you have the 1 stage procedure you have your brachytherapy planning and treatment on the same day. And you might stay in hospital for a night afterwards.

You'll also have an ultrasound scan a few weeks before treatment to check you're suitable for treatment and to work out how many seeds you need. 

2 stage procedure 

Some hospitals do your planning 2 to 4 weeks before your brachytherapy. At the planning session you have an ultrasound to check how many seeds you need in your prostate.

Then at your second visit your doctor puts in the radioactive seeds. This is called a 2 stage procedure.

Before treatment

You meet members of your treatment team. You sign the consent form to agree to the treatment and can ask questions. It helps to write down all your questions beforehand to take with you. The more you know about what is going to happen, the more confident you will feel.

The radiotherapy team

A member of the radiotherapy team tells you about:

  • the treatment you're going to have
  • the benefits
  • the possible risks
  • what to expect afterwards

The nurse specialist

The nurse checks your:

  • general health
  • weight
  • blood pressure
  • pulse
  • temperature

You might also have a heart tracing (ECG).


You need to tell the treatment team if you are taking any medicines. If you are taking blood thinning drugs you might need to stop taking them up to 2 weeks before having the radiotherapy.

You might start taking a medicine called tamsulosin. It helps you to pass urine. And your doctor might give you antibiotics. They will tell you how long you need to take these medicines for. 


You have stop eating from at least 6 hours before the treatment if you're having general anaesthetic. 

Emptying your bowel

You might need to have an enema to empty your bowel so that it is clear during the treatment. An enema is a liquid that you put into your back passage. Or you might have a liquid medicine (laxative). You need to stay close to a toilet for a few hours afterwards.

During treatment

You go to the operating theatre. Your anaesthetist might put a thin tube into your back to give a spinal anaesthetic so that you feel nothing below the waist. Or you might have a general anaesthetic so that you are asleep.

Your doctor may put a thin tube called a catheter into your penis through the urethra (the tube that carries urine from your bladder). The catheter shows the position of the urethra within the prostate gland on ultrasound. It also drains urine from the bladder during the procedure.

Your doctor puts an ultrasound probe into your back passage (rectum). It gives a clear picture of your prostate on a screen. The doctor then uses fine needles to put between 80 and 120 small radioactive seeds into your prostate. The needles go through the area of skin between the scrotum and back passage (the perineum).

Diagram of seed implantation

The doctor takes out the ultrasound probe and the needles once it's done. 

After treatment

You stay in the operating department until the sedation or anaesthetic wears off. You might wear an oxygen mask for a short time. A nurse then takes you back to your ward. You might have a catheter to drain your urine but your nurse usually takes this out after a few hours.

You can usually go home once you can pass urine normally but might need to stay in hospital overnight.

Side effects

You have some swelling and bruising between your legs where the needles were put in. Your nurse will give you painkillers. Warm baths can also help.

You might have a burning feeling when you pass urine and may see traces of blood for the first few days. You might also need to pass urine more often than usual. Or have problems passing wee. Try to drink at least 2 litres of water a day. 

Avoid or cut down on drinks that might irritate the bladder such as fizzy drinks and alcohol. Also limit caffeinated drinks like tea, coffee and coke. 

You might feel tired for the first few days after treatment as you recover from the anaesthetic. Rest when you need to.

You might notice blood in your semen for a few weeks after the treatment. Ejaculation can also be painful at first but tends to settle in time. After a while you may notice that you have very little or no semen due to the radiotherapy.

You may have constipation, loose poo or diarrhoea for a few weeks due to inflammation of the bowel. Tell your doctor or nurse if you have it. They can give you medicines.

Rare side effects

Permanent seed brachytherapy is generally a very safe procedure. But a very few people have:

  • bladder damage
  • bowel damage
  • injury to the muscle that controls poo
  • an opening that forms between the urethra and bowel (fistula)

These are very unlikely to happen to you.

Safety Precautions

Your doctor will tell you what precautions you need to take after treatment. They might advise you to keep a 1 metre distance from pregnant women or children. This includes not having children on your lap. But you can be in the same room as them for as long as you want. This is usually for around 2 months or so after treatment. 

There's a very small risk that a seed might come out when you go to the toilet. If a seed does come out, don’t touch it. Pick it up using tweezers, tongs or a spoon and flush it down the toilet. Contact your consultant to let them know.

It's safe to have sex and sleep in the same bed as your partner after treatment. For a few months, when having sex you should wear a condom. This is in case a seed comes out.

There is a very small risk that one or more seeds might get loose and move out of the prostate gland. There have been reports of seeds moving into the bladder or lung. When a seed has gone to another part of the body, it does no harm. 

Medical card

When you go home, your doctor gives you a card. You need to keep the card with you at all times for 2 years. It has your personal details and the details of your consultant. It says what procedure you have had in case of an emergency.

Check ups

Around 6 weeks after the treatment you have a CT scan to check that all the seeds are in the right place. You have regular blood tests to check the level of a protein called prostate specific antigen (PSA) in your blood.

Last reviewed: 
24 Jul 2019
  • Prostate cancer: diagnosis and management
    National Institute for Health and Care Excellence (NICE), 2019 

  • EAU guidelines on prostate cancer. part 1: screening, diagnosis, and local treatment with curative intent - update 2013
    A Heidenreich and others
    European Urology, 2014. Volume 65, Pages 123-137 

  • Multi-disciplinary Team (MDT) Guidance for Managing Prostate Cancer
    British Uro-oncology Group (BUG) and the British Association of Urological Surgeons (BAUS) Section of Oncology, 2013

  • The Royal College of Radiologists' audit of prostate brachytherapy in the year 2012
    AJ Stewart and others
    Clinical Oncology, 2015. Volume 27, Pages 330-336

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