Radiotherapy is a treatment where radiation is used to kill cancer cells.
There are many different ways you can have radiotherapy, but they all work in a similar way.
They damage cancer cells and stop them from growing or spreading in the body.
Radiotherapy may be used in the early stages of cancer or after it has started to spread.
It can be used to:
Radiotherapy is generally considered the most effective cancer treatment after surgery, but how well it works varies from person to person.
Ask your doctors about the chances of treatment being successful for you.
Radiotherapy can be given in several ways. Your doctors will recommend the best type for you.
The most common types are:
Treatment is usually given in hospital. You can normally go home soon after external radiotherapy, but you may need to stay in hospital for a few days if you have implants or radioisotope therapy.
Most people have several treatment sessions, which are typically spread over the course of a few weeks.
Read more about what happens during radiotherapy.
As well as killing cancer cells, radiotherapy can damage some healthy cells in the area being treated.
This can cause some side effects, such as:
Many of these side effects can be treated or prevented and most will pass after treatment stops.
External radiotherapy doesn't make you radioactive, as the radiation passes through your body.
The radiation from implants or injections can stay in your body for a few days, so you may need to stay in hospital and avoid close contact with other people for a few days as a precaution.
Read more about the side effects of radiotherapy.