Cold Snare Piecemeal Resection vs Cold Snare Endoscopic Mucosal Resection

The study will compare the use of cold snare piecemeal resection (CSPR) vs cold endoscopic mucosal resection (Cold EMR). The study will include two cohorts: one cohort for conventional adenomas 10-19mm in size and one cohort for serrated lesions 10mm or larger.

Inclusion Criteria: 1. ≥ 18 years of age 2. Presenting for a screening, surveillance, diagnostic, or therapeutic colonoscopy 3. Found to have: * a sessile serrated lesion or hyperplastic polyp ≥ 10 mm during procedure (Serrated Cohort) or * a 10-19 mm conventional adenoma during procedure (Adenoma Cohort) 4. Ability to provide informed consent Exclusion Criteria: 1. Pedunculated or semi-pedunculated polyps (as defined by Paris Classification type Ip or Isp) 2. Polyps confirmed to be anything other than: * sessile serrated lesion or hyperplastic polyp on histologic diagnosis (Serrated Cohort) or * conventional adenoma on histologic diagnosis (Adenoma Cohort) 3. Patients with Ulcerative Colitis or Crohn's disease 4. Polyps with features suggestive of submucosal invasion 5. Polyps that are not able to be removed endoscopically due to location (e.g. extending into appendiceal orifice or diverticulum) 6. Patients with a known or suspected diagnosis of any of the following polyposis syndromes with known genetic mutations: * Familial Adenomatous Polyposis Syndrome * MUTYH associated Polyposis Syndrome * Juvenile Polyposis Syndrome * Cowden's Syndrome * Peutz-Jeghers Syndrome 7. Subjects whose colonoscopy procedure is not able to be completed due to bowel prep precluding polyp identification.