Long-term outcomes of endoscopic submucosal dissection and transanal endoscopic microsurgery for the treatment of rectal tumors.

[BACKGROUND AND AIM] Endoscopic submucosal dissection and transanal endoscopic microsurgery are good options for the treatment of rectal adenomas and early rectal carcinomas, but whether long-term outcomes of these procedures are comparable is not known. The aim of this study was to address this question.

[METHODS] A retrospective single-center study evaluating 98 consecutive procedures between June 2008 and December 2017 was performed in a tertiary cancer center. Consecutive patients who had undergone either endoscopic submucosal resection or transanal endoscopic microsurgery for rectal adenomas and early rectal carcinomas were evaluated, and long-term recurrence and complication rates were compared.

[RESULTS] Both groups were similar regarding sex, age, preoperative surgical risk, and en bloc resection rate (95.7% in the endoscopic and 100% in the surgical group, P = 0.81). Mean follow-up period was 37.6 months. Lesions resected endoscopically were significantly larger (68.5 mm) than those resected by transanal resection (44.5 mm), P = 0.003. Curative resections occurred in 97.2% of endoscopic resections and 85.2% of the surgical ones (P = 0.04). Comparing resections that fulfilled histologic curative criteria, there were no recurrences in the endoscopic group (out of 69 cases) and two recurrences in the transanal group (8.3% of 24 cases), P = 0.06. Late complications occurred in 12.7% of endoscopic procedures and 25.9% of surgical procedures (P = 0.13).

[CONCLUSIONS] In our experience, endoscopic submucosal resection seems to have advantages over transanal endoscopic microsurgery, with similar en bloc resection rate and lower rate of late complications and recurrences. Multicenter randomized controlled trials are needed to support our findings.