Radiotherapy

Radiotherapy is a treatment for cancer. It uses high doses of radiation to kill cancer cells. Over half of people who are treated for cancer have radiotherapy. Radiotherapy is often used with other treatments, such as chemotherapy and surgery.

About radiotherapy

Radiotherapy uses high-energy radiation to target the area of your body affected by cancer. The aim is to target and destroy the cancer cells without damaging your healthy cells (as much as possible).

You may have radiotherapy:

• to cure some types of cancer
• on its own, or with chemotherapy
• before surgery to make the tumour (growth of cells) easier to operate on
• after surgery to destroy any remaining cancer cells
• to help control your symptoms and improve your quality of life if your cancer can’t be cured
• to treat non-cancerous conditions, such as keloid scars

Types of radiotherapy

There are several different types of radiotherapy procedure.

• External beam radiotherapy is the most common type of radiotherapy. Radiation is directed into the affected area of your body from outside your body. This usually uses a radiotherapy machine called a linear accelerator (linac). Stereotactic ablative radiotherapy (SABR) is another type of external radiotherapy that uses smaller, focused beams of radiation to precisely target certain cancers. These include brain, lung, prostate, liver and pancreatic cancer.
• Internal radiotherapy (brachytherapy) is when radiation is delivered from inside your body. Radioactive implants are placed near to, or inside, the affected area of your body.
• Radioisotope therapy is treatment with radioactive medicines. You have these medicines as an injection, drink or capsule to swallow. These medicines target cancer cells in your body.

The type of radiotherapy treatment you have will depend on the type of cancer you have, and which part of your body is affected. Your radiotherapy will be designed for your particular circumstances and tailored to you. The following information describes external beam radiotherapy and internal radiotherapy (brachytherapy) in more detail.

Preparing for radiotherapy

If your doctor recommends you have radiotherapy, they’ll discuss this with you and check you’re happy to go ahead. If you are, you’ll be referred to your nearest radiotherapy department. Not all hospitals have a radiotherapy department, so you may need to go to a specialist cancer hospital or a large regional hospital. You’ll usually start by seeing a radiation oncologist – a specialist cancer doctor who’ll plan and oversee your treatment.

External beam radiotherapy

If you're having external radiotherapy, you may be asked to come to the radiotherapy department for a CT planning scan. This will help to plan your treatment. It is sometimes called ‘simulation’.

You may be given special instructions about things you need to do before your planning scan, such as:

• having an enema to clear your bowel
• needing your bladder to be full or empty

Your radiotherapy team will want to take scans in the exact same position that you’ll be in when you have your radiotherapy treatment. During your planning scan, they may:

• use cushions and other equipment to support you
• draw tiny dots on your skin to show you’re in the right position for your treatment
• fit you with a plastic radiotherapy mask if you’re going to have radiotherapy to your head or neck

It may take anything from a few hours to a few weeks to plan radiotherapy treatment with external beam radiotherapy after you have your scan.

Your doctor may also take X-rays, MRI scans, or CT scans at the start of each of your radiotherapy sessions. This is called image-guided radiotherapy. You may need to have these scans with some types of cancer, such as lung cancer – when the area being targeted with the radiotherapy moves every time you breathe. Image-guided radiotherapy helps your doctor:

• make sure you’re in the best position for your radiotherapy treatment
• target the right area more accurately, giving better results and fewer side-effects

Sometimes, your doctor may implant little metal markers (called seeds) before you begin your radiotherapy. This can help to show up the target area on an X-ray during treatment.

Internal radiotherapy (brachytherapy)

If you’re having internal radiotherapy (brachytherapy), you’ll be asked to have a scan beforehand. This is so your doctor can work out:

• how much radiation you need
• where to put the implants

With internal radiotherapy, you can sometimes have the treatment on the same day as your scan, or you’ll need to come back another day.

What happens during radiotherapy?

External beam radiotherapy

You usually have external beam radiotherapy in small amounts (called fractions) over a number of days or weeks. This is usually on weekdays, so you should get weekends off. You’re most likely to have treatment as an outpatient, rather than stay in hospital. The whole session usually takes anything from 15 minutes to an hour.

You’ll have radiotherapy in a treatment room with a large radiotherapy machine called a linear accelerator (linac). You’ll need to lie in a certain position – usually the same way you lay in your planning scan. Your treatment is delivered by radiographers. They’ll help you to get in the right position. Once you’re ready, the radiographers will leave the room and deliver the treatment. They’ll be able to watch you, and you can talk with them if you need to.

Having radiotherapy doesn’t hurt. But you may find it uncomfortable to stay in position while you have it. Your radiotherapy team will try to make you as comfortable as possible.

Internal radiotherapy

If you’re having internal radiotherapy (brachytherapy), you may need to stay in hospital for a few days.

The implants may be delivered using a needle, a catheter (thin tube) or an applicator. This will depend on the part of your body being treated. The implant can be taken out straightaway, or it can be left in for a set amount of time. Occasionally, it may be left in permanently, but the radioactivity will gradually wear off.

If you’re having internal radiotherapy, you may need to follow some safety precautions when you go home, until the radioactivity wears off. It’s usually safe to be with other people. But you may need to avoid very close contact with children and pregnant women for a short while. Your radiotherapy team will give you advice about this.