The exact cause of bowel cancer is not known. However, some factors increase the chance of developing bowel cancer, including:
Polyps in the colon are a risk factor for bowel cancer. If polyps are removed, the risk of bowel cancer is reduced.
If one or more of your family members (such as a parent or sibling) have been diagnosed with bowel cancer before the age of 55, it may run in your family. This is also a possibility if two relatives on the same side of your family have bowel cancer.
If you are concerned about bowel cancer because of your family history, see your general practitioner (GP) for regular checkups and discuss whether genetic testing would be suitable for you. Doing regular physical activity, maintaining a healthy weight and eating a diet high in fruit, vegetables and fibre may help protect against bowel cancer.
There are two very rare conditions that can run in families. About 5% to 6% of bowel cancers are caused by these inherited genetic conditions.
This condition causes many polyps to form in the bowel. If polyps caused by FAP are not removed, they usually become cancerous.
This increases the risk of developing bowel cancer and other cancers. Not everyone with HNPCC will develop bowel cancer.
In its early stages, bowel cancer often has no noticeable symptoms. Symptoms some people experience include:
Cancer of the bowel may cause a blockage (bowel obstruction). This causes symptoms such as abdominal pain, feeling bloated, constipation and being sick.
Many of the symptoms of bowel cancer are common to other large bowel conditions, such as haemorrhoids or tears in anal tissue. Some foods or medications can also change bowel habits or cause stools to turn red or black. If you have any of the above symptoms, talk to your doctor.
Last Reviewed: 01 February 2011