Colorectal polyps Flashcards
Description of colorectal polyps
Overgrowth of epithelial cells in the colon or rectum
Are they more commonly benign or malignant?
Benign
Most common colorectal polyps
Adenomatous polyp (colonic adenomas)
What gene mutation causes benign polyps
APC gene
What gene mutations cause malignant polyps
K-RAS and p53
What is FAPS
Familial adenomatous polyposis syndrome is an inherited condition where many polyps occur. Usually colon is removed as probability of malignancy is high
The three histological forms of adenomatous polyps
Tubular (holes), villous (tree-like) and tubulovillous (both)
What are the two ways to describe the histological forms
Pedunculated (has stalk membrane attachment) and sessile (firmly attached)
What is the most malignant combination
Sessile villous
Small polyps are often malignant. True or false
False. They are rarely malignant and large polyps are often malignant
Describe inflammatory polyps
Polyps in UC and crohns that are not malignant
Describe hamartomatous polyps
Mix of tissue distorted architecture, associated with juvenile polyps and peutz-jeghe’s syndrome. They are usually benign
Risk factors for polyps
Genetic conditions, injury to bowel wall, cigarette smoke, IBD and old age.
How to diagnose
Usually no symptoms and discovered on colonoscopy. A biopsy is used to diagnose and a polypectomy (polyp removal)
