Feasibility and Safety of Endoscopic Submucosal Dissection for Recurrent Rectal Lesions that after Transanal Endoscopic Microsurgery: A Case Series.

[OBJECTIVES] Recently, several studies have demonstrated the usefulness of endoscopic submucosal dissection (ESD) for residual or locally recurrent colorectal lesions after endoscopic treatment. However, the feasibility of ESD for recurrent rectal lesions after transanal endoscopic microsurgery (TEM) has not been fully investigated. In this study, we evaluated the feasibility and safety of ESD for recurrent rectal lesions after TEM.

[METHODS] The treatment outcomes of 10 lesions in 9 patients, who underwent ESD between January 2006 and March 2018 for recurrent rectal lesions after transanal endoscopic microsurgery, were evaluated.

[RESULTS] All lesions were successfully resected en bloc, and the R0 resection rate was 90%. The median size of the resected specimens and lesions (range) was 44 mm (21-70) and 27.5 mm (5-60), respectively. The pathological diagnoses included 4 adenomas and 6 cancerous lesions. The cancerous lesions included 5 cases of mucosal cancer and 1 case of superficial submucosal invasive cancer (depth of submucosal invasion <1,000 μm from the muscularis mucosae). No adverse events occurred. There was no recurrence during the follow-up period.

[CONCLUSIONS] ESD for recurrent rectal lesions after TEM by expert's hands appears to be safe and feasible.