External radiotherapy for prostate cancer
Information about external radiotherapy treatment for prostate cancer.
What is external radiotherapy?
External radiotherapy uses high-energy rays to kill cancer cells. The radiation beams are aimed at the cancer using a machine called a linear accelerator.
With early prostate cancer, radiotherapy aims to fully get rid of the cancer.
Stereotactic ablative radiotherapy (SABR)
SABR is an advanced radiation technique that targets a small area with a high dose of radiotherapy over relatively few sessions. Typically, SABR is given in 5 sessions over a 2-week period.
SABR is only recommended in certain cases. Your consultant will tell you if SABR is an option for you.
Who can have radiotherapy?
- The treatment is suitable if your prostate cancer is found only within your prostate gland or has spread just outside it to the pelvic lymph nodes.
- Radiotherapy can also be used if PSA tests show that there may be cancer cells left after treatment. For example, after surgery to remove the prostate. The aim is to destroy any cancer cells that may have escaped the original treatment, providing an opportunity for cure (or disease control, in cases of recurrence). This is called salvage radiotherapy.
- Radiotherapy and hormone therapy are often used together to treat locally advanced prostate cancer. This helps to make the radiotherapy work better at controlling your prostate cancer.
- It may not be the best option if you have urinary symptoms, as it may make them worse.
Before radiotherapy
Planning is an important part of radiotherapy, to make sure the highest dose is given to the tumour area and as little as possible to nearby cells.
Planning CT scan
This scan takes pictures of inside your pelvis to pinpoint the exact area in the body to be treated. It may take 2-3 weeks from your scan before you start your radiotherapy treatment.
On the day of the planning scan
Before your scan, you will be asked to drink water and hold it to ensure that your bladder is full. It is important that you do not go to the toilet before the scan, as you will need to hold this full bladder for up to 30 minutes during the procedure. In some centres, you may also be given a rectal suppository to help clear air from your bowel before the scan. This rectal suppository is a small tube that delivers medicine to help you to empty your back passage.
During the scan, you must lie flat on the scanner couch and remain still. The radiation therapist will ensure you are positioned correctly, and they may make one or more small, permanent marks on your skin. These marks, called tattoos, are tiny (about the size of a freckle) and are used to help line up the radiation beams during your treatment.
Extra planning for SABR radiotherapy
If you are having SABR radiotherapy, you may have extra planning steps to ensure the treatment is precise. For example, small gold markers called fiducials placed into your prostate to guide the radiation. Your consultant will discuss your preparations with you.
Having prostate radiotherapy
- During your radiotherapy treatment you will be positioned carefully on a bed.
- The LINAC machine will rotate around you, delivering the X-ray beams. This rotating technique helps to minimise the radiation dose to your normal healthy organs, such as the bladder or the bowel.
- It is very important that you lie in the exact same position for each treatment. You may be asked to fill your bladder before treatment each day. The purpose of this is to push the small intestines (gut) up out of the way of the radiotherapy beams.
- As you go through your treatment, you will have more scans to monitor your position and the area being treated.
- Each radiotherapy treatment usually only takes around 10 minutes. However, you will likely be in the radiotherapy department for longer (60-90 minutes), depending on machine waiting times, bladder filling, and positioning on the treatment bed.
Both external beam and SABR radiotherapy are equally as successful in treating cancer, they are just given in different ways.
Getting to your radiotherapy appointments
- Ask your radiation therapist for a time that suits you.
- Ask about free or discounted car parking.
In some areas there are hospital or local charity transport services available. - You may be eligible for healthcare travel costs if you are travelling a distance to treatment daily. Read about the Travel2Care fund.
Radiotherapy side-effects
Radiotherapy side-effects can be:
- Acute side-effects (appear during or soon after your radiotherapy treatment)
- Late/persistent side-effects (appear/carry on for months after treatment finishes)
Most acute side-effects settle down in the weeks after radiotherapy. Sometimes side-effects may improve significantly but not fully
disappear.
Short-term or acute side-effects
Urinary symptoms can include:
- A burning sensation when you pass urine.
- Needing to pass urine more often.
- A sudden need to pee, without much warning
- Blood in your urine
Sometimes, radiotherapy can cause some discomfort when peeing, especially towards the end of the course of radiotherapy. Swelling or irritation may make the flow of urine slow down. If it is becoming difficult to pee, alert your radiotherapy team immediately for advice.
Read more about urinary symptoms and how to manage them.
- Diarrhoea (loose, semi-solid poos).
- Constipation (not pooing often enough or passing small amounts).
- Passing more wind or mucus
- A strong need to empty your bowels quickly (urgency).
- A sensation that you need to poo, but nothing comes out.
The radiotherapy team will help you find ways to manage your bowel symptoms during your treatment. These symptoms usually settle down a short time after your treatment has stopped.
Read more about coping with side-effects and symptoms such as diarrhoea and constipation.
You may feel tired during and after your treatment. Even after a good night’s sleep you may feel your energy is low. This fatigue differs from normal tiredness. It may affect your mood, concentration and motivation. Try to do some form of exercise daily, such as a
brisk walk. Research shows that daily exercise will improve your energy during and after treatment.
Read more about coping with fatigue.
Late, long-term or permanent side-effects
Radiotherapy to your prostate can damage the nerves and blood vessels that control erections. This can make it difficult for you to get and keep an erection strong enough for sex, especially if you are
taking hormone therapy as well. This is called erectile dysfunction (ED) or impotence. ED can happen some time after treatment.
If you have had problems with ED before radiotherapy, you are more likely to have problems with erections afterwards. Other health problems, medications, and your overall health can also affect erectile function.
There are treatments to help with ED. For example, there is some evidence that taking tablets or using vacuum therapy soon after radiotherapy may reduce your risk of erectile problems.
You may not be interested in sex at first. But taking the tablets or using a vacuum pump at an early stage may improve your chances of getting
erections when you are ready to think about sex again. Discuss this
with your hospital doctor, nurse or GP.
Read more about erectile dysfunction and how to manage it.
- Needing to go to the toilet more often.
- Pain when passing urine.
- Blood in your urine.
- Narrowed water pipe (urethra), which can make it hard to pass urine.
- Leaking urine. This is rare unless you had surgery too.
In most cases, any bladder changes are temporary. Only a small number of people have long-term urinary problems after radiotherapy. Tell your doctor or nurse if you have any long-term changes, so that they can advise you about ways to manage and treatments to help.
- Diarrhoea (loose, semi-solid poos).
- Feeling an urge to empty bowels but not being able to or feelings that the bowels haven’t emptied properly.
- Passing clear or jelly like mucus.
- Needing to get to the toilet more quickly.
- Needing to get to the toilet more often.
- Bleeding when you go to the toilet.
Bowel problems may carry on or appear years after treatment. Your bowel habits may change permanently.
Bowel problems are common as you get older, so symptoms may be due to something else. But it’s important to tell your doctor about symptoms such as diarrhoea or bleeding. You may need to have tests to find out the cause or have treatment to help.
- Less or no semen when you ejaculate
Dry orgasm means you won’t be able to have a child naturally, as there is no semen. Talk to your doctor before your treatment if you’re worried about this. It’s not safe to assume you are sterile, so you will need to use contraception to avoid pregnancy.
Read more about fertility and cancer treatment.
Advantages and disadvantages of external beam radiotherapy
Advantages
- Can cure cancer.
- You don’t need a general anaesthetic and you don’t need to stay overnight in hospital.
- It’s often possible to work and continue with normal activities during the treatment.
- Receiving radiotherapy treatment is painless.
- You are not radioactive during or after the treatment so you can be in close contact with others.
- Each treatment session is relatively short. It usually takes about 10-30 minutes, depending on the type of treatment, although you may be in the radiotherapy department for longer.
Disadvantages
- It may be difficult if you have to travel a long way to the radiotherapy centre.
- Treatment usually takes several weeks, with multiple sessions. SABR involves fewer sessions.
- You may not be able to have prostate surgery in the future due to the effects of the radiotherapy.
- You might experience side-effects such as bowel or urinary problems, erectile dysfunction and fatigue. Some of these side-effects may develop or get worse over the longer term.
- You may become infertile.
- Treatment may very slightly increase the risk of getting a second cancer, although this is not common.
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