Sergey Kantsevoy, MD, performs a rectal endoscopic submucosal dissection. The patient is a 54-year-old woman with a strong family history of colon cancer. She had two prior colonoscopies which were incomplete due to suboptimal bowel prep. Her last colonoscopy was in 2017. This video is part of the 11th Annual Long Island Live Endoscopy Course, Frontiers of Endoscopic Surgery.