The bowel is comprised of two sections: the small intestine and the large intestine. The term bowel cancer is used to refer to cancers which have developed in the large intestine. As the large intestine encompasses the colon and rectum, sometimes the terms colon or rectal cancer are used to distinguish the exact location of the tumour. Cancers can occur in the small intestine, however this is rare.

Generally, bowel cancers are slow growing and develop from polyps which are existing growths on the inner lining of the bowel wall. If left untreated, polyps may continue to develop and become malignant (cancerous). A cancerous bowel tumour can remain localised in the bowel for some time, however it can spread to lymph nodes, glands and other organs. The key to preventing the spread of the cancer to other parts of the body is early detection and treatment.

From the age of 50, the risk of developing bowel cancer increases significantly, with 50 per cent of bowel cancers occurring in people in the 50-69 age range.

National Bowel Cancer Screening Program offers free screening for people turning 50, 55 and 65 between 2008 and 2010.
People do not have to have symptoms or a family history of bowel cancer to be at risk of the disease. Up to 75 per cent of bowel cancers are preventable through changes in diet and lifestyle, in particular by maintaining a healthy weight and enjoying regular physical exercise.

The disease can be present without any symptoms, making participation in the screening program even more important.

Anyone with a higher risk of developing the disease, because of their previous history of bowel cancer or polyps or a strong family history of bowel cancer, should consult their doctor – as should anyone who is experiencing symptoms.

Although there are specific risk factors which increase a person’s risk of developing bowel cancer, everybody can develop the disease.

Risk factors include:

• Increasing age – bowel cancer is most common in people aged over 50 years;
• Poor diet and lifestyle factors;
• A personal history of bowel cancer or polyps in the colon or rectum;
• Having first or second degree relatives (a parent, sibling, grandparent, aunt, uncle, nephew or niece) with a history of bowel cancer or polyps;
• The presence of chronic inflammatory bowel disease (including Crohn’s disease and extensive ulcerative colitis); and
• Having an immediate family member with Familial Adenomatous Polyposis (FAP) or Hereditary Non Polyposis Colon Cancer (HNPCC).

People with an increased risk of developing bowel cancer should contact their health professional to discuss a regular, ongoing monitoring program.
Regular screening can reduce your risk of developing bowel cancer.

Symptoms to be aware of include:

• Rectal bleeding such as blood in the stool, on the toilet paper or in the toilet bowl (blood may be either bright or dark red).
• A recent change in usual bowel patterns which last for more than two weeks such as constipation, diarrhoea, changes in frequency, solidity or stool size.
• Lack of energy or tiredness.
• Feeling of incomplete emptying of the bowel.
• Unexplained weight loss or lack of appetite.
• Persistent cramping or abdominal pain. The presence of any of these symptoms does not necessarily mean you have bowel cancer. These symptoms can be caused by a wide range of other conditions, however it is important that you see your health professional promptly to have your symptoms investigated.
  Some people with early symptoms of bowel cancer may delay seeking medical help, as they feel embarrassed, but it is important to talk about these problems as soon as you notice them.