Endoscopic intermuscular dissection for deep submucosal invasive cancer in the rectum: a new endoscopic approach

Abstract

Risk for lymph node metastasis associated with deep submucosal invasion should be balanced against mortality and morbidity of total mesorectal excision (TME). Dissection through the submucosa (ESD), hinders radical deep resection margins, and full thickness resection (TEM/TAMIS) may influence the outcome of completion TME. Endoscopic intermuscular dissection (EID) in between the circular and longitudinal part of the muscularis propria could potentially provide an R0 resection while leaving the rectal wall intact. In this prospective cohort study, data of patients treated with EID for suspect deep submucosal invasive rectal cancer between 2018-2020 were analysed. Study outcomes were the percentages of technical success, R0 resections, curative resections, and adverse events. In total 67 cases (age 67 yrs; 73% male) were included. Median lesion size was 25 mm (IQR 20-33). Overall technical success, R0 resection, and curative resection rates were (96%; 95%CI 90-100%), 81% (95%CI 72-90%) and 45% (95%CI 33-57%). Only minor adverse events occurred in 8 patients (12%). EID for deep invasive T1 rectal cancer appears to be feasible and safe, and the high R0 resection rate creates a rectal preserving potential in 45% of patients. Received: 12 January 2021 Accepted after revision: 24 January 2022 Publication Date: 24 January 2022 (online) © 2022. Thieme. All rights reserved. Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany