Radiotherapy

Radiotherapy uses radiation to destroy cancer cells.

This page will help you understand how radiotherapy is used for cancer.

When is radiotherapy used?

Radiotherapy might be your only treatment or used in combination with other cancer treatments. 

It can be used to:

• Try to completely destroy the cancer (curative radiotherapy)
• Shrink a tumour to make surgery easier (neo-adjuvant radiotherapy)
• Lower the risk of cancer returning (adjuvant radiotherapy)
• Treat symptoms (palliative radiotherapy)
• Prepare for a stem cell or bone marrow transplant

How does radiotherapy work?

Radiotherapy uses radiation to target cancer cells in the area of the body it is given.

It can be given externally or internally.

It aims to stop the cancer cells growing by breaking down their DNA.

Radiotherapy does affect normal cells too but the effects are normally temporary. This is because they can repair themselves but cancer cells can't.

External radiotherapy

Radiotherapy is most commonly given externally using beams of high energy, like x-rays.

Sessions can last from a few seconds to several minutes. 

It does not hurt but it may be uncomfortable if you need to hold the same position for a while.

Internal radiotherapy

Radiotherapy can also be given internally as:

• Radioactive liquid to drink
• Capsules
• Injection into a vein
• Implants of metal wires, tubes or seeds (brachytherapy)

How often is radiotherapy given?

Radiotherapy may be given in one visit but is usually divided into doses (called fractions) as a course of treatment over several days or weeks.

You don't usually have to stay in hospital to have radiotherapy.

For treatment to some areas of the body, or towards the end of a longer course of treatment, a hospital stay may be needed.

Side effects

Most side effects for radiotherapy are local to the area of the body being treated but fatigue affects almost everyone.

Side effects are usually delayed, build up over the course of treatment and for a few weeks after it's finished before improving. 

Talk to your doctor, specialist nurse or the radiographer about possible side effects and what can be done to reduce them.

Maggie's is here with you

You might have questions about your treatment and how you'll manage before, during or after.

Our Cancer Support Specialists are here listen to your concerns and help you find the information and help that's right for you:

• Find your nearest Maggie's centre – you don't need an appointment, just come in

Last review: Oct 2021 | Next review: Oct 2021