Grant: Fellowship - Priority Announcement: Gastroenterology

Colorectal cancer (CRC) is common, with a 1 in 14 lifetime risk of developing the disease among Canadians. CRC is often life-threatening, but can be prevented. Evidence shows convincingly that removal of colon polyps during screening colonoscopy helps prevent CRC. However, removal of polyps (polypectomy) is associated with risks, including bleeding and perforation of the bowel. Post-polypectomy bleeding can be immediate (seen at the time of polypectomy) or delayed (1 to 14 days after polypectomy). Small metallic devices called endoscopic clips can be applied to polypectomy sites to stop immediate active bleeding, and in some cases, to close small perforations of the bowel. However, physicians performing colonoscopy also often apply these clips purely to prevent delayed post-polypectomy bleeding, even when no active bleeding is seen during colonoscopy. There is limited medical literature to support this practice, and therefore, it is unclear whether endoscopic clips in this context are justified at all, or whether they should be reserved for certain subgroups of high-risk patients. The purpose of this project is to conduct a thorough practice assessment regarding the use of endoscopic clips during polypectomy, and to determine the effectiveness of clips for preventing delayed post-polypectomy bleeding and perforation. The specific objectives are: 1) to assess utilization patterns of endoscopic clips at a large outpatient screening centre; 2) to identify which clinical and system factors correlate with use of endoscopic clips for prevention of post-polypectomy bleeding and perforation; and 3) to determine the effectiveness of endoscopic clips for prevention of delayed post-polypectomy bleeding and perforation, by analyzing the rates of complications in these patients. By studying these objectives, we will derive important information to allow us to more safely treat patients in the future, and potentially to reduce healthcare system expenditure.