Risk Factors for Colorectal Cancer: Family history of colorectal cancer, Age, IBD, and history of abdominal irradiation.
Important Colonoscopy Links
- Colorectal Cancer Screening Tests and Intervals.
- Preparing for a colonoscopy.
- When to Repeat a Colonoscopy.
- Cologuard
Common types of GI polyps
Hyperplastic polyps
Inflammatory polyps
Hamartomatous polyps
Tubular adenomas
Villous adenomas
Which histologic type of colonic polyps >1.0 cm in size has the highest likelihood of becoming malignant? Answer: Villous adenomas (“Villous are adenoma is vile”)
Colon cancer = Adenocarcinoma. It arises from an adenoma or adenoma polyp. If a polyp has adenoma in its name, it’s chances of becoming an adenocarcinoma is higher and so you will scope more frequently.
“Histologically, serrated polyps have a serrated or sawtooth appearance from the folding in of the crypt epithelium. Types of serrated polyps include hyperplastic polyps, traditional serrated adenomas, and sessile serrated polyps (also known as sessile serrated adenomas)…
…Serrated polyps get their name from their jagged appearance on microscopy. In the past, all serrated colorectal lesions were called hyperplastic polyps. But with the advent of molecular and genetic diagnostics and with the ability to recognize the subtle morphologic differences of serrated lesions, they have been reclassified into those without malignant potential (hyperplastic polyps) and those that are neoplastic (sessile serrated polyps and traditional serrated adenomas) ” Cleveland Clinic Journal of Medicine 2012
“Colon cancer arises from adenomatous polyps, and generally requires at least 5 years of growth before malignant transformation. Villous adenomas carry a threefold increased risk for becoming malignant compared with other adenomatous types such as tubular or tubulovillous adenomas. The larger the polyp the greater the chance of malignancy, although malignant polyps <1.5 cm are rare. Hamartomas (juvenile polyps) and inflammatory polyps (often associated with inflammatory bowel disease) are benign. Hyperplastic polyps are the most common histologic type by far, but only rarely become cancerous.”ABFM Critique
Reference / Further Reading
Cleveland Clinic Journal of Medicine. 2012 December;79(12):865-871. Sessile serrated polyps: Cancer risk and appropriate surveillance. Link on MDEdge.com.
https://www.mdedge.com/sites/default/files/issues/articles/media_9f33b4a_865.pdf