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Radiotherapy for rectal cancer

Radiotherapy uses high energy waves similar to x-rays to destroy bowel cancer cells. You usually have radiotherapy to treat cancer that started in the back passage (rectum). It is not normally a treatment for cancer of the large bowel (colon).

You might have external or internal beam radiotherapy. External beam radiotherapy directs radiotherapy beams at the cancer from a machine. This is different to internal radiotherapy which means giving radiotherapy to the cancer from inside the body.

Planning radiotherapy

The radiotherapy team plans your external beam radiotherapy before you start treatment. This means working out the dose of radiotherapy you need and exactly where you need it.

Having external radiotherapy treatment

External beam radiotherapy directs radiotherapy beams at the cancer from a machine. This is different to internal radiotherapy which means giving radiotherapy to the cancer from inside the body.

Side effects of radiotherapy

Side effects tend to start a week after the radiotherapy begins. They can include feeling tired, sore skin, diarrhoea and passing urine more often.

Internal radiotherapy for rectal cancer

Internal radiotherapy means giving radiotherapy to the cancer from inside of the back passage (rectum). It is also called brachytherapy.

Long term side effects of radiotherapy

Most side effects gradually go away in the weeks or months after treatment. But some side effects can continue. Or you might notice some that begin months or years later.

Radiotherapy for advanced bowel cancer

Radiotherapy uses high energy rays similar to x-rays to kill cancer cells. It can shrink the cancer, relieve symptoms and help you feel more comfortable.

Last reviewed: 
31 Aug 2018
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