Endoscopic submucosal dissection of neoplastic lesions of the colon: clinical application and techniques

: Endoscopic submucosal dissection (ESD), first developed in Japan, is increasingly performed worldwide to allow en bloc removal of large lesions from the gastrointestinal tract. Colorectal ESD results in higher en bloc and R0 resection rates than those in endoscopic mucosal resection (EMR), thus reducing the risk of local recurrence and allowing accurate pathological evaluations. Compared with surgical resection, ESD is better tolerated by patients, with reduced adverse event rates, hospitalization durations, and costs. Colorectal ESD is most appropriate for lesions larger than 20 mm with a risk of submucosal invasion and that are difficult to remove en bloc or for lesions in which previous EMR had failed or was not possible. However, inferior en bloc and R0 resection rates of colorectal ESD have been reported in the US compared to those in Japan, potentially due to increased technical challenges secondary to higher prevalence of obesity and significantly greater occurrence of fibrotic lesions in the US due to previous resection attempts. Recently, colorectal ESD guidelines have been updated, and various techniques and technologies have been developed to improve colorectal ESD outcomes, reduce procedure time, and overcome technical challenges. This article will discuss updated indications, new devices, resection strategies, technique variations, and clinical outcomes of colorectal ESD with regional comparisons (i.e., North America, Europe, and Japan).