Radiotherapy: the basics

Radiotherapy, which kills cancer cells using radiation, can be given to you externally or internally. In external radiotherapy, machines are used to target cancerous cells with special X-rays. In internal radiotherapy, radioactive liquids and implants are used inside your body to attack cancerous cells. Whichever type you have, there’s a lot of sci-fi-sounding jargon – photon beams, protons, particle beams, high-energy X-ray beams – so just keep asking for explanations if you’re ever confused.

Radiotherapy is used for a variety of reasons. It’s used on its own or in combination with chemotherapy to try to cure cancers. It can be used before surgery to shrink a tumour so it’s easier to remove, or after surgery to kill off any cancer cells that survived the surgery. And it can be used to relieve cancer symptoms in more advanced cancers.

External treatment

External beam radiotherapy is the most common type of external treatment. During your appointments, you’ll need to stay still for a few minutes while high-energy radiation is targeted at your cancer and a small area of surrounding healthy cells – in case the cancer has spread. The machine that’s used doesn’t touch you, you won’t feel any pain and you usually won’t need to stay in hospital overnight. There are various other types of external radiotherapy too, which doctors use to target very specific areas.

Internal treatment

Internal radiotherapy involves radioactive liquids and implants. You might be given a liquid to drink, a tablet to swallow or an injection. This won’t cause any long-term harm, but you might need to stay in a hospital room by yourself for a few days while you become less radioactive. Implants are things like wires and tubes, placed in your body to release radiation near cancer cells, then left in your body for between a few minutes and a few days – or sometimes for good.

How long does it take?

If you have external beam radiotherapy, you’ll be given it in a number of individual treatments. These are called fractions. People often have five treatments a week – one a day, Monday to Friday – with a chance to rest over the weekend and to let healthy cells recover. You might need treatment over the weekend too, though. In total, external radiotherapy usually lasts between one and seven weeks.

Any side effects?

A lot of the common side effects of external radiotherapy are fairly mild and don’t last too long, but they can still be unpleasant. It can cause:

Sore skin. You might find your skin gets red or darker. It might get dry and itchy too, or peel like you’ve spent too long in the sun. This usually heals in a couple of weeks. In the meantime, use unperfumed soap and don’t shave skin that hurts. If it’s summer, slap on some suncream (factor 30+), and if it’s winter, protect your skin from chilly winds.

Hair loss. Your hair might fall out in the area you’re having treated. So if you’re having treatment on your head or neck, there’s a good chance you’ll lose the hair on your head – and this can be tough. Hair usually starts growing back a few weeks after treatment ends, but while you wait – and if you decide the bald look isn’t for you – you could always expand your hat collection or try a super-realistic wig from our Hair 4 U scheme.

Tiredness. Your body uses a lot of energy to repair healthy cells that are damaged by radiotherapy, so give yourself plenty of sofa time if you’re feeling wiped out – ask friends to bring over films, magazines and video games.

Sickness. Most people aren’t sick during radiotherapy, but it can happen. It’s more likely if you’re having radiotherapy to your stomach or pelvis, but this usually stops a few days after your treatment. If you do feel rough, talk to your doctor, who will be able to give you some anti-nausea drugs. Diarrhoea can be a problem too, and your doctor can also prescribe something to help with that.

Lack of appetite. It’s not surprising, really – if you’re feeling sick and tired, eating’s never going to be the first thing on your mind. If you do find you’re not feeling hungry, try and keep your energy levels up by eating little and often.

And the rest… Diarrhoea is a pretty common side effect of radiotherapy to your stomach or pelvis. Swallowing can hurt if you have radiotherapy to your throat. Your joints might become stiff where you’re being treated. And you might find you lose interest in sex. All of these are likely to get back to normal once your treatment ends.

Long-term effects. Sometimes, radiotherapy can have side effects that don’t get better once the treatment has finished. These vary depending on where your cancer is but, if you’re worried, talk to your doctor or nurse about possible long-term side effects before you start any treatment.

What will it do?

Radiotherapy does permanent damage to cancer cells – causing them to die or stop growing. Healthy cells nearby are also damaged, but these are usually able to repair themselves and get back to normal.


Questions to ask

Never be afraid to ask questions about your cancer. Ask, ask and ask again. And if you don’t understand the answers you get, keep asking until you do.

If your doctor recommends radiotherapy, you might like to ask:

  • What kind of radiotherapy is being recommended
  • Whether it’s being combined with other treatments
  • How long your treatment will last
  • What the side effects might be, and how you can reduce them
  • What the radiotherapy is meant to achieve
  • How effective it’s likely to be
  • Whether any other treatments might work.