Cancer treatment
Radiotherapy
Radiotherapy uses carefully targeted radiation to destroy cancer cells. It is a common cancer treatment, usually painless during each session, and can cure or control cancer or relieve symptoms.
Quick answer
Radiotherapy: what it is, why it's done and what happens
Radiotherapy uses high-energy radiation, precisely aimed at a tumour, to damage cancer cells so they cannot grow, while sparing healthy tissue as much as possible.
- Why it is done: It is used to cure some cancers, to shrink tumours or reduce the chance of return alongside surgery, or to relieve symptoms such as pain.
- What happens: Most often it is given from a machine outside the body (external beam), in short daily sessions over days to weeks.
What it is
Radiotherapy uses high-energy radiation, precisely aimed at a tumour, to damage cancer cells so they cannot grow, while sparing healthy tissue as much as possible.
Why it is done
It is used to cure some cancers, to shrink tumours or reduce the chance of return alongside surgery, or to relieve symptoms such as pain.
What happens
Most often it is given from a machine outside the body (external beam), in short daily sessions over days to weeks. Each session is painless and takes a few minutes; careful planning ensures accurate targeting.
Recovery
Side effects build up during a course and usually affect the treated area (such as skin soreness or tiredness); most settle in the weeks after treatment. The team advises on managing them.
Good to know
Risks and things to consider
Radiotherapy is a precise, well-established treatment, but side effects depend on the area treated. It is planned individually to maximise benefit and limit effects on healthy tissue.
Education and reference only. This explains the procedure in general terms and is not medical advice. Your own care, risks and recovery will be explained by the team looking after you.
Answers
Radiotherapy: frequently asked questions
Does radiotherapy make you radioactive?
External beam radiotherapy does not make you radioactive — it is safe to be around others, including children. (A few specialised internal treatments have specific precautions, which the team explains.)
Is radiotherapy painful?
The treatment itself is painless during each session. Side effects such as skin soreness or tiredness can develop over a course and usually settle afterwards.
Related
Other cancer treatment
Sources
Where this is drawn from
- NHS — Tests and treatments
- NICE — procedure and treatment guidance
- Relevant Royal College / professional body
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