Intestinal polyps can occur in any part of the gastrointestinal tract. Since most patients exhibit no obvious symptoms, polyps are often only discovered when complications arise, during colonoscopy, or during surgical procedures.
In adults, polyps are commonly adenomas, with approximately half of those larger than 2 cm in diameter having malignant potential. Villous adenomas present an even higher risk of malignancy. In children, polyps are predominantly hamartomatous, occurring mostly in individuals under the age of 10, and they sometimes prolapse through the anus.
Inflammatory polyps are induced by epithelial stimulation resulting from inflammatory reactions and may arise secondary to any type of inflammatory or infectious disease. They generally do not exhibit a tendency toward malignancy, with treatment focused on the primary intestinal disease.
Serrated polyps are categorized into three types: hyperplastic polyps, sessile serrated adenomas/polyps (SSA/P), and traditional serrated adenomas (TSA). Hyperplastic polyps are the most common type of nonneoplastic polyps in the colorectum, typically appearing as multiple small lesions less than 5 mm in diameter and generally not requiring specific treatment. SSA/P are regarded as precursor lesions of colorectal cancer associated with BRAF gene mutations, while TSA is more closely linked to colorectal cancer associated with KRAS gene mutations.
Pedunculated polyps or sessile adenomatous polyps smaller than 2 cm in diameter can be excised through endoscopic procedures. Larger sessile or broad-based polyps require malignancy evaluation, with surgical intervention considered when necessary.