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Bowel (colorectal) cancer

Bowel cancer is a common cancer in Ireland.  About 2,560 people are diagnosed with bowel cancer each year. 

Bowel cancer can be treated with surgery, chemotherapy, targeted therapies, external radiotherapy and chemoradiation.

On this page:

What is bowel (colorectal) cancer?

Bowel cancer is when normal cells in your bowel change and grow in an abnormal way. A group of these cancer cells can form a tumour. Bowel cancer is a common cancer in Ireland. About 2,560 people are diagnosed with it each year. 

Cancer that begins in the large bowel is called colon cancer. This cancer may cause a blockage in your bowel, which can affect how your bowel works. Cancer of the rectum occurs very low down in your bowel close to your anus.

What is the bowel and what does it do?

A cross section of a body showing the parts of the digestive system

The bowel is part of your digestive system. It is made up of the small bowel and the large bowel. 

The large bowel contains your colon and rectum. Most cancers occur in the large bowel.

When you swallow food, it goes from the gullet (oesophagus) to your stomach and into your small bowel. Food is digested in the small bowel and nutrients are taken into the body. In the large bowel, water is absorbed from digested food.

The waste matter that is left (called faeces, stool or poo) is stored in the rectum (back passage) until ready to pass out of the body through the anus - the opening to the outside of your body. 

More information about bowel cancer treatment

Treatment for bowel cancer includes surgery, chemotherapy, targeted therapies and radiotherapy. For more information about treatments for bowel cancer, visit our treatment page.

Looking for support?

Our cancer support section contains information and advice on coping with cancer for diagnosed patients and their loved ones.

Publications about bowel cancer
Downloadable booklets and factsheets
Bowel cancer symptoms logo
Bowel cancer - Know what to look for
Know the symptoms of bowel cancer, because spotting cancer early is important. An A4 poster to download, share, or print.
Bowel cancer leaflet
Bowel Cancer - What You Should Know leaflet
This leaflet gives you facts about bowel cancer, its causes and symptoms, how it is diagnosed, and how to reduce your risk. It also has information on bowel screening.
Bowel (colorectal) and anal cancer booklet
Bowel (colorectal) and anal cancer booklet
Information for bowel cancer and anal cancer patients, including tests, staging, treatment and side-effects, and how to cope.

For more information

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1800 200 700

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Medical content updated from our 'Understanding bowel (colorectal) and anal cancer' booklet (2022), reviewed by Mr Saqib Zeeshan, Consultant General & Colorectal Surgeon, Mary Sweeney, Colorectal Nurse Specialist and Teraze Toby, Daffodil Centre Nurse.