A polyp is a small growth on the inner lining of the colon or rectum. Polyps are common, especially after the age of 45, and most cause no symptoms. Most bowel cancers start as a polyp and grow slowly over several years, so finding and removing polyps at colonoscopy helps prevent cancer.
Types of polyps
- Adenomas are the most common type that can turn into cancer over time. The risk is higher when they are large or many.
- Serrated polyps can also turn into cancer. Some are flat and pale, and are easier to see when the bowel preparation is good.
- Hyperplastic polyps, especially small ones in the rectum, are usually harmless.
The type can only be confirmed when the removed polyp is examined in the laboratory.
Symptoms
Most polyps cause no symptoms. Larger ones can bleed, which may show as blood in the stool, a positive stool test (FIT), or iron deficiency anaemia.
Removal
Most polyps are removed during the colonoscopy with a small wire loop, which is painless. Very large or flat polyps may need a longer procedure or a separate session. Bleeding afterwards is uncommon, and is usually minor. See the colonoscopy preparation sheet.
When is the next colonoscopy?
This depends on the number, size and type of polyps, and on how clean the bowel was. It is commonly between 3 and 10 years, and sooner for large or many polyps, or if the preparation was poor. Dr Chia advises the interval once the laboratory results are back.
Family members
If you had a large or advanced polyp, your parents, brothers, sisters and children may need to start screening earlier. Ask Dr Chia what applies to your family.
Lowering your risk
- Do not smoke, and keep alcohol low
- Keep to a healthy weight and stay active
- Eat less red and processed meat, and more fibre
General information only. Reviewed by Dr Chia Chung King, 2026-11-07. Book a consultation.