Evolution of endoscopic mucosal resection (EMR) technique and the reduced recurrence of large colonic polyps from 2012 to 2020

Background Endoscopic mucosal resection (EMR) is an effective method for removing non-pedunculated polyps >= 20 mm. We aimed to examine changes in EMR techniques over a 9-year period and evaluate frequency of histologic-confirmed recurrence. Methods We identified patients who underwent EMR of non-pedunculated polyps >= 20 mm at a safety net and the Veteran's Affairs (VA) hospital in Houston, Texas between 2012 and 2020. Odds ratios (ORs) and 95% confidence intervals (CI) for associations with recurrence risk were estimated using multivariable logistic regression. Results 461 unique patients were included. The histologic-confirmed recurrence was 29.0% at 15.6 months median follow up (IQR 12.3 - 17.4). Polyps removed between 2018 and 2020 had a 0.43 decreased odds of recurrence vs. polyps removed between 2012 and 2014. The use of viscous lifting agents increased over time (from 0 to 54%), and the use of saline was associated with increased risk of recurrence (OR 2.28 [CI 1.33 - 3.31]). Conclusions Histologic-confirmed recurrence after EMR for non-pedunculated polyps >= 20 mm decreased over the seven year-period. Saline was associated with a higher risk of recurrence and the use of more viscous agents increased over time.