Early detection of bowel cancer

Bowel (or colorectal) cancer occurs in the colon or rectum. It is the second most common cancer in Australia (not including non-melanoma skin cancer). Around 14,000 new cases of bowel cancer are diagnosed each year in Australia.

If detected early, the chance of successful treatment and long-term survival improves significantly.

What are the bowel cancer symptoms I need to look out for?

Not all bowel cancers show symptoms. Experiencing symptoms does not necessarily mean you have bowel cancer. However, you should see your doctor if you notice:

• bleeding from the back passage or any sign of blood after a bowel motion
• a change in usual bowel habit, such as straining (constipation) to go to the toilet or loose motions (diarrhoea)
• abdominal pain or bloating
• weight loss for no obvious reason, or loss of appetite
• symptoms of anaemia, including unexplained tiredness, weakness or breathlessness.

Who is at risk?

Everyone is at risk of developing bowel cancer, however the risk greatly increases with age, particularly from age 50. You are also at greater risk if you have:

• a previous history of polyps in the bowel
• a previous history of bowel cancer
• chronic inflammatory bowel disease (e.g. Crohn’s disease)
• a strong family history of bowel cancer
• increased insulin levels or type 2 diabetes.

If you are at increased risk, discuss surveillance options with your doctor.

How is bowel cancer detected?

Bowel cancer can be detected using a variety of methods.

A faecal occult blood test (FOBT) is a simple test that can be done at home and looks for hidden traces of blood in a bowel motion. It can help detect bowel cancer in its early stages in people without symptoms. 

You should have an FOBT every two years from age 50. If an FOBT finds blood, further investigation, usually a colonoscopy, is needed to establish the cause.

The National Bowel Screening Program, using FOBT, is offered free to all Australians aged 50-74 every two years. A FOBT test kit will be sent directly to your home and you should receive one within about six months of your birthday. For more information visit www.bowelcancer.org.au

Colonoscopy involves a long, thin, flexible tube with a video camera lens on the end, enabling a specialist to look inside your bowel. If a polyp or bowel cancer is found, it can be removed during the procedure. Colonoscopy is usually performed under sedation as day procedure. It is also used as a surveillance test for people at increased risk of developing bowel cancer.

Sigmoidoscopy is similar to colonoscopy, however it only explores the lower part of the bowel, where cancer is more likely to develop. If a pre-cancerous polyp is detected during the procedure, a full bowel examination by colonoscopy is usually needed.

Other diagnostic tests for bowel cancer are available. Discuss these options with your doctor.

What else can I do?

Bowel cancer is one of the most preventable cancers.

Your most effective protection is to:

• do an FOBT every two years from age 50
• get 30 to 60 minutes of moderate to vigorous exercise per day
• maintain a healthy body weight
• eat a well-balanced diet
• avoid processed and burnt meat; limit red meat intake to three to four times per week
• limit alcohol
• quit smoking.