Definition of a polyp
A lesion which projects into the lumen of the bowel, The term is morphological, and for
an actual diagnosis to be made, histology is needed.
Description
-Size of a few mm to several cm in diameter.
-Single or multiple. In polyposis syndrome hundreds may be found
-Larger polyps are found in the rectum
-5% may contain invasive carcinoma at discovery.
-The type of cell that forms the polyp varies and is important in determining its potential
for developing into a cancer
Epidemiology
Highly prevalent in the population, especially among older population (up to 50% over
60s have an adenomatouspolyp).
Risk factors:
-Over 50’s
-If there is a personal history of polyps
-If there is a family historyof polyps or colon cancer
-Smoker
-Drinker
-Overweight/fatty food intake?
-Differences in dietary fibre and antioxidants/calcium/folate?
-Differences in race and sex are less prominent
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, Clinical presentation
-Most polyps are asymptomatic until they grow to 2cmin diameter
-They can lead to bleeding, frank blood or microscopic bleeding (presenting with anemia)
-Polyps rarely present with a change in bowel habit –but large polyps in the rectum can
present with tenesmus.
-A large amount of mucuscan also be passed.
-Rarely a polyp will prolapse through the anus or act as an apex for an intussception.
Complications
1-Lower GI Hemorrhage
2-Oclusions
3-Malignancy
Diagnostic tools
1. Colonoscopy + biopsy
2. Barium enema and X-ray
3. Sigmoidoscopy
4. Rigid proctoscopy–for rectal polyps
5. CT Colonography
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