Colorectal (Bowel) Cancer

The colon and rectum are two parts of the large intestine (or large bowel), that receive digested food from the small intestine and caecum. The colon absorbs water and nutrients from the faeces, as it is passed to the rectum. The rectum is the last 15cm or so of bowel, which receives waste from the earlier parts of the colon and stores faeces (“stool” or “poo”) before it exits the body, via the anus.  

Colorectal (also called bowel) cancer can affect any part of the colon or rectum, and becomes more common as people get older. Cancer usually occurs when normal gland cells of the lining of the colon change into abnormal cells, and grow out of control. These are called adenocarcinomas. Often, bowel cancers start as polyps, which are common, and usually harmless. Occasionally, these polyps can become cancerous. Other types of cancers can affect the bowel, like lymphomas, and sarcomas. 


Importance for PLHIV50+

Bowel cancer affects both men and women and is most common over the age of 50. It affects approximately 1 in every 13 people in Australia in their lifetime, and is more common in people living with HIV. Age and your genes (a family history of bowel cancer) and some medical conditions (e.g. Crohn’s, Ulcerative colitis, type II diabetes), play important roles in determining your risk of bowel cancer. However diet and lifestyle factors can also increase a person’s risk, including smoking, excessive alcohol, obesity, eating lots of red meat or processed foods 



Unfortunately, bowel cancer often causes no symptoms and symptoms can be non-specific. Sometimes people experience abdominal pain, a change in their bowel habits, bleeding in their bowel movements, unexplained weight loss or fatigue. A national screening program for colorectal cancer is available, which may help to detect cancer early, and reduce the risk of dying from bowel cancer. In most people, including those living with HIV, it is recommended that people have a screening test every two years, between the ages of 50 and 74 years old. This involves a specimen of faeces, collected at home, being sent away and tested for blood.  

Some people require earlier, more frequent, or different testing (e.g. with colonoscopy), and it is important that you discuss your individual needs with your healthcare provider.  

If detected, specialists use additional tests, like scans, to determine if and how far the cancer might have spread.  Treatment of bowel cancer is individualised, and often includes surgery to remove the cancer. Some people need chemotherapy or radiotherapy before or after surgery.