What is bowel cancer?

Bowel cancer is the second biggest cause of cancer death in Australia.  

It can happen in any part of the colon or rectum (parts of the lower digestive system). It can start growing either from the inner lining of the bowel or from small growths on the bowel wall called adenomas or polyps.  

If it is not found, bowel cancer can spread into the wall of the bowel, lymph nodes (glands) and then to other organs.  

If found early, over 90% of bowel cancers can be successfully treated. 

Bowel cancer can develop without signs, but many people with bowel cancer do notice signs. These signs are often called symptoms and can include: 

• blood in your poo or in the toilet bowl 
• a change in your toilet habits that doesn't go away for more than 3 weeks. This can include looser poos, severe constipation and/or if you need to poo more often than usual 
• unexplained tiredness or weight loss 
• stomach pain. 

If you notice any of these, it is important that you speak to your doctor straight away. 

Bowel screening spots the early signs of bowel cancer, before you start to notice signs or symptoms. Screening is the best way to find bowel cancer early. When we find bowel cancer early, successful treatment is highly likely. 

We recommend all Australians aged 50 to 74 take part in the National Bowel Cancer Screening Program. If you’re aged 50-74, you will receive a free at-home screening test every two years in the mail. Do the test – it could save your life. 

We don't know the exact cause of bowel cancer. Yet, research has shown that people with certain risk factors are more likely to develop bowel cancer. Some things that can increase your risk of bowel cancer can include: 

• age 
• family history  
• inflammatory bowel disease 
• poor diet 
• physical inactivity 
• alcohol 
• obesity  
• smoking.

You can reduce your bowel cancer risk by 

• quitting smoking 
• being active 
• enjoying a healthy diet with plenty of fresh fruit and vegetables 
• limiting red and processed meats 
• limiting alcohol 
• maintaining a healthy body weight 

You can find more information on bowel cancer and prevention here. 

It does not matter what age you are, if you experience any signs or symptoms you should speak to your doctor. These signs can include a change in bowel habits, blood in your poo, stomach pain or unexplained fatigue or weight loss. 

You may have a significant family history of bowel cancer, if: 

• A close relative (parent, brother, sister or child) developed bowel cancer at a young age (under 55 years); or  
• More than one close relative in your family has had bowel cancer at any age. 
   

More than 75 per cent of people who develop bowel cancer do not have a family history of bowel cancer. If you think you have a family history of bowel cancer, you should speak to your doctor. They can talk to you about your risk of getting the disease.