What is a polyp?
Polyps are abnormal growths originating from the inside lining of the bowel from mutations of the epithelium. They are increasingly common with age and rarely cause symptoms. The vast majority of bowel cancers are thought to arise from polyps so removing them at Colonoscopy can potentially prevent the development of cancer.
If polyps are found they will almost always be able to be removed at the time of the examination. Most polyps can be burnt off by placing a wire snare around the base and applying an electric current. If you have any questions please ask me before the colonoscopy.
Because polyps rarely cause any symptoms there is a rationale for 5-yearly Colonoscopy in anyone who is at increased risk of bowel cancer.
Type of polyps
Hyperplastic polyps tend to be benign and have limited if any risk for future transformation to cancer. They are usually found in the lowest part of the bowel called sigmoid colon and in the rectum.
Adenomatous polyps (which do have malignant potential) can be divided into low and higher risk lesions:
Low risk adenomas:
- < 10mm in size
- tubular adenoma histology
- low grade dysplasia
Higher risk adenomas:
- > 10mm in size
- villous adenoma histology
- sessile serrated adenoma histology
- high grade dysplasia
Our Clinic usually deals with the polyps at the time of the Colonoscopy (unless unsafe to do so).
- Polypectomy to remove all most all the polyps at the time of colonoscopy if possible
- Use of endoloop (polyloop) or endoclips to prevent bleeding after polypectomy or prevent perforation
- Removal of large pedunculated or sessile polyps
- Removal of large flat polyps by EMR (endoscopic mucosal resection)
Risk associated with polypectomy
- Bleeding immediate or delayed
- Perforation immediate or delayed