{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T23:44:21Z","timestamp":1785800661078,"version":"3.56.0"},"reference-count":32,"publisher":"Georg Thieme Verlag KG","issue":"CP","license":[{"start":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T00:00:00Z","timestamp":1784073600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Endosc Int Open"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Introduction Underwater endoscopic mucosal resection (uEMR) technique has gained popularity for removal of large non-pedunculated colorectal polyps (LNPCPs) due to high en-bloc resection rates and lower recurrence rates. However, there is no information regarding outcomes of uEMR for giant colorectal polyps. Therefore, we aimed to evaluate the outcomes of uEMR for giant colorectal polyps across multiple centers in North America.<\/jats:p>\n                  <jats:p>Methods We conducted a multicenter retrospective study of adults with giant colorectal polyps undergoing uEMR between January 2019 and November 2025. Giant colorectal polyps were defined as LNPCPs \u226540 mm. Primary outcomes were technical success and rate of recurrent adenoma. Secondary outcomes were severe adverse events (SAEs) and predictors of technical success, recurrence, and SAEs.<\/jats:p>\n                  <jats:p>Results A total of 137 polyps, with mean polyp size 47.6 mm were included. Majority of the lesions were located in right colon (61%, n = 83) with the most common histopathology being high-grade dysplasia (HGD) (31.4%, n = 43). Technical success was achieved in 90.5% (n = 124) with en-bloc resection rate of 11.7% (n = 16). Polyp fibrosis (OR: 0.08) and HGD (OR: 0.15) were independent predictors of inability to achieve technical success. Of 92 (67.1%) patients with follow-up, recurrent polyp was present in 8.7% (n = 8). SAEs were noted in 9.5%, consisting of delayed bleeding (9.5%, n = 13), while no delayed perforation or post polypectomy syndrome was noted.<\/jats:p>\n                  <jats:p>Discussion Our study demonstrates that uEMR is technically feasible for the removal of giant colorectal polyps with an acceptable safety profile and recurrence rate.<\/jats:p>","DOI":"10.1055\/a-2910-5182","type":"journal-article","created":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T23:11:52Z","timestamp":1784157112000},"source":"Crossref","is-referenced-by-count":0,"special_numbering":"S","title":["Outcomes of Underwater Endoscopic Mucosal Resection for Giant Colorectal Polyps: A Multicenter Study"],"prefix":"10.1055","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6775-0776","authenticated-orcid":false,"given":"Rahul","family":"Karna","sequence":"first","affiliation":[{"name":"University of Minnesota, Minnesota, United States","place":["Minneapolis"],"department":["Division of Gastroenterology and Hepatology"]},{"name":"Minneapolis VA Medical Center, Minnesota, United States","place":["Minneapolis"],"department":["Department of Pharmacy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1648-3310","authenticated-orcid":false,"given":"Natalie","family":"Wilson","sequence":"first","affiliation":[{"name":"The University of North Carolina at Chapel Hill School of Medicine, North Carolina, United States","place":["Chapel Hill"],"department":["Division of Gastroenterology and Hepatology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amir S.","family":"Seid","sequence":"additional","affiliation":[{"name":"Mayo Clinic, Minnesota, United States","place":["Rochester"],"department":["Division of Gastroenterology and Hepatology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kaylee","family":"Larsen","sequence":"additional","affiliation":[{"name":"University of Colorado Anschutz Medical Campus, Colorado, United States","place":["Aurora"],"department":["Department of Internal Medicine"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5892-0537","authenticated-orcid":false,"given":"Thomas","family":"Enke","sequence":"additional","affiliation":[{"name":"University of Colorado Anschutz Medical Campus, Colorado, United States","place":["Aurora"],"department":["Division of Gastroenterology and Hepatology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ali","family":"Hassam","sequence":"additional","affiliation":[{"name":"East Carolina University, North Carolina, United States","place":["Greenville"],"department":["Division of Gastroenterology and Hepatology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anand R.","family":"Kumar","sequence":"additional","affiliation":[{"name":"Thomas Jefferson University Hospitals, Pennsylvania, United States","place":["Philadelphia"],"department":["Division of Gastroenterology and Hepatology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shawn L.","family":"Shah","sequence":"additional","affiliation":[{"name":"Dallas VA Medical Center, Texas, United States","place":["Dallas"],"department":["Division of Gastroenterology and Hepatology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joy","family":"Zhao","sequence":"additional","affiliation":[{"name":"Thomas Jefferson University, Pennsylvania, United States","place":["Philadelphia"],"department":["Department of Internal Medicine"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alyssa Y.","family":"Choi","sequence":"additional","affiliation":[{"name":"VA Puget Sound Health Care, Washington, United States","place":["Seattle"],"department":["Division of Gastroenterology and Hepatology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Danny","family":"Issa","sequence":"additional","affiliation":[{"name":"University of California Los Angeles David Geffen School of Medicine, California, United States","place":["Los Angeles"],"department":["Division of Gastroenterology and Hepatology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ahmed","family":"Saeed","sequence":"additional","affiliation":[{"name":"AdventHealth Centra Care Kansas, Kansas, United States","place":["Shawnee"],"department":["Division of Gastroenterology and Hepatology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jennifer","family":"Phan","sequence":"additional","affiliation":[{"name":"Hoag Digestive Health Institute, California, United States","place":["Newport Beach"],"department":["Division of Gastroenterology and Hepatology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeffrey D.","family":"Mosko","sequence":"additional","affiliation":[{"name":"St Michael\u2019s Hospital, Canada","place":["Toronto"],"department":["Division of Gastroenterology and Hepatology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frances","family":"Dang","sequence":"additional","affiliation":[{"name":"University of California Irvine, California, United States","place":["Irvine"],"department":["Division of Gastroenterology and Hepatology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anders","family":"Westanmo","sequence":"additional","affiliation":[{"name":"Minneapolis VA Medical Center, Minnesota, United States","place":["Minneapolis"],"department":["Department of Pharmacy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew","family":"Reinink","sequence":"additional","affiliation":[{"name":"Minneapolis VA Medical Center, Minnesota, United States","place":["Minneapolis"],"department":["Division of Gastroenterology & Hepatology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jason B.","family":"Samarasena","sequence":"additional","affiliation":[{"name":"University of California 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