Endoscopic submucosal dissection in rectal tumors extending or not to the dentate line: A comparative analysis

The feasibility of endoscopic submucosal dissection (ESD) in rectal tumors extending to the dentate line (RTDL) is unclear.

To analyze the outcomes of ESD in RTDL compared to non-RTDL, with a special focus on the lower rectum location.

Observational multicenter retrospective study. All patients with a rectal tumor who underwent ESD in 2013-2017 were included. A comparative analysis between RTDL and non-RTDL groups was done.

Two-hundred and twenty-eight patients (median age: 69 years, range: 33-89, 51.3% male) with RTDL (n = 65, 28.5%) and non-RTDL lesions (n = 163, 71.5%) were included. There were no significant differences between the en-bloc (89.2% vs. 90.8%, p = 0.718), complete (60% vs. 71.8%, p = 0.084) and curative resection rates (58.5% vs. 68.7%, p = 0.141). The overall complication rate (4.6% vs. 8%, p = 0.370) was not different, independently of the rectal location. Local recurrence was higher in RTDL (7.3% vs. 1.5%, p = 0.065). The indication for surgery due to non-curative resections in the lower rectum was lower in RTDL (9.2% vs. 14.6%, p = 0.378).

The safety, effectiveness and long-term impact of ESD in RTDL and non-RTDLs is comparable. Local recurrence in the lower rectum may be higher in RTDL.