Evaluation and long-term outcomes of the different modalities used in colonic endoscopic mucosal resection

Endoscopic mucosal resection (EMR) has been used in western countries to remove colonic polyps for at least the last two decades. Significant experience has been accumulated and the efficacy of the method has recently been evaluated in a large meta-analysis. A number of variations to modify the technique, including knife-assisted, cap-assisted, ligation devices, and underwater EMR, have been developed in an attempt to improve outcomes. However, to date there are only limited data comparing these techniques or demonstrating the superiority of any one of them. This article reviews the current evidence on the efficacy of each of these modified techniques.