Colon Cancer Screening: Who Should Get Screened

Average-risk adults

If you have no symptoms and no personal or family history of concern, many international guidelines suggest considering screening from around age 45 to 50. This is a guide, not a universal rule; your doctor will advise the right timing for you.

Higher-risk adults

You may be advised to start earlier or screen more often if you have:

• A family history of colon cancer or polyps, especially in a close relative.
• A personal history of polyps or inflammatory bowel disease (such as ulcerative colitis or Crohn's disease).
• Certain inherited conditions (for example, Lynch syndrome or familial polyposis).

Anyone with symptoms

Screening is for people without symptoms. If you notice blood in the stool, a persistent change in bowel habit, unexplained weight loss, ongoing abdominal pain, or unexplained anaemia, these should be assessed promptly regardless of age - this is investigation, not routine screening.

Stool-based tests

Tests such as the FIT (faecal immunochemical test) look for tiny amounts of blood in the stool. They are simple, done at home, and involve no prep or sedation. They are typically repeated regularly, and an abnormal result usually leads to a colonoscopy.

Colonoscopy

A colonoscopy examines the whole colon directly and allows polyps to be removed in the same visit. It requires bowel prep and often sedation, but is done less frequently when results are normal. For people at higher risk, or when a stool test is abnormal, colonoscopy is usually the recommended step.

Your doctor will talk through which option suits your risk, and there is no one-size-fits-all answer.