Endoscopic mucosal resection of non-polypoid colorectal neoplasm.

Endoscopic mucosal resection (EMR) is preferred to standard polypectomy for the resection of non-polypoid lesions because these lesions can be technically difficult to capture with a snare; furthermore, without submucosal injection the underlying muscularis propria may be excessively coagulated or even inadvertently resected. Because the resection plane of EMR is in the middle or deeper part of the submucosa, EMR allows the precise depth of the lesion to be evaluated. Although the majority of non-polypoid lesions are adenomatous, non-polypoid colorectal neoplasm has a high association with advanced pathology, irrespective of size. Using EMR, a complete pathologic specimen is obtained, the risk of lymph node metastasis can be accurately assessed based on the depth of invasion, and patients can be suitably managed. Used according to its indications, EMR provides curative resection, and obviates the higher morbidity, mortality, and cost associated with surgical treatment.