Safety and efficacy of endoscopic submucosal dissection of rectal tumors extending to the dentate line.

Background And Study Aims: Unique anatomical features render endoscopic resection for rectal tumors extending to the dentate line (RTDL) technically challenging. The aim of this study was to evaluate the feasibility of endoscopic submucosal dissection (ESD) for RTDLs.

Patients And Methods: This retrospective study compared ESD for RTDLs with proximal rectal tumors between September 2002 and June 2012. En bloc resection rate, R0 resection rate, complications, and tumor recurrences were assessed.

Results: A total of 45 RTDLs (median age 69 years; 15 males; median lesion size 38.4 mm) and 94 proximal rectal tumors were identified. En bloc resection and R0 resection rates were 95.6 % (43/45) and 53.3 % (24/45), respectively. The perforation rate was 4.4 %. Compared with proximal rectal ESD, ESD for RTDLs showed longer procedure time (104 vs. 60 minutes; P < 0.001), lower R0 resection rate (53.3 % vs. 70.2 %; P = 0.019), and more frequent high grade fever (22.2 % vs. 4.3 %; P = 0.002). No residual adenoma was observed at the first surveillance colonoscopy. Recurrence rate did not differ significantly between the two groups.

Conclusions: ESD for RTDLs demonstrated safety and effectiveness comparable to ESD in proximal rectal lesions.