colonoscopy findings not polyps but lymph

The chromosomal instability (CIN) pathway is the most attributed pathway and accounts for almost 80% of colorectal adenocarcinomas in the U.S. Two main molecular pathways lead to adenocarcinoma of the colon. Excluding the cases with a diagnosis of juvenile polyps, there are still reports of coexisting adenoma-adenocarcinomas in 2 to 15% of children and teenagers who had an initial diagnosis of polyp in colonoscopy. The small tubular adenomas have a lower incidence of high-grade dysplasia. Tubular adenomas comprise smaller adenomas (less than 1 cm) mainly, in contrast to villous adenomas that tend to have a larger polyp size. In general, the size of adenoma correlates with both its histopathological type and degree of dysplasia.

Thus, they need more aggressive and frequent colonoscopic surveillance. In patients with reported advanced adenoma, i.e., higher dysplasia grade and higher villosity in the first colonoscopy, the probability of advanced adenocarcinomas is higher later in life.

The length of the adenoma-adenocarcinoma interval depends on the size of the adenoma, its morphological features, and the pathological type. More than 95% of colon adenocarcinomas arise from colonic polyps, while approximately 1.5% to 9.4% of adenomas turn to a malignant lesion within an interval of 8 to 10 years. Īdenoma-carcinoma sequence explains the molecular changes that lead to the formation of carcinoma from adenomas. If adjusted for surface area, all types of adenomas have the same potential to become cancerous. Īlthough villous adenomas are more likely to become cancerous, this reflects the fact that they generally have the largest surface area due to their villous projections. Tubular adenomas are the most common type of colonic adenomas, comprising a prevalence of more than 80%. A tubulovillous adenoma is referred to as an adenoma with both features. A polyp with more than 75% villous features, i.e., long finger-like or leaf-like projections on the surface, is called a villous adenoma, while tubular adenomas are mainly comprised of tubular glands and have less than 25% villous features. ĭepending on the pattern of growth, these tumors can be villous, tubular, or tubulovillous. Although a tumor of benign nature, these adenomas are usually considered precancerous and can transform into malignant structures, in contrast to hyperplastic polyps, with no malignant potential. Colonic adenomas are raised protrusions of colonic mucosa, i.e., polyps formed by glandular tissue.

Colonoscopy findings not polyps but lymph