BACKGROUND AND STUDY AIM: Endoscopic submucosal resection (ESR) is a novel resection technique. ESR is performed with a partially insulated snare, which allows a resection close to the proper muscle layer thus resecting in the deep submucosa. This should have advantages over endoscopic mucosal resection (EMR). This pilot study aimed to compare the quality of specimens obtained by ESR versus EMR with emphasis on preservation of submucosal tissue. PATIENTS AND METHODS: In this retrospective single-center study we analyzed specimens from large flat or sessile rectal neoplasms resected by either ESR or EMR. The primary outcome was a comparison of specimen quality assessed by a validated semiquantitative histopathology score which rates specimen quality between 0-5 points. Secondary outcomes included en bloc and R0 resection rates, complications and recurrences. RESULTS: < 0.001). There was no significant difference in R0 resection, complication or recurrence rates. CONCLUSIONS: ESR provides superior specimen quality compared with EMR, allowing more accurate histopathological evaluation, particularly in neoplastic lesions with suspected submucosal invasion.
Metter et al. (Sun,) studied this question.