CLINICAL OUTCOMES OF ENDOSCOPIC SUBMUCOSAL DISSECTION FOR RECTAL TUMORS EXTENDING TO THE DENTATE LINE

Aims Endoscopic submucosal dissection (ESD) is a well-established and widely accepted resection technique for colorectal lesions. However, the endoscopic excision of lesions extending to the dentate line involves specific difficulties related to the particular anatomical features of the anorectum. As a result, current guidelines give no recommendations on the ideal treatment strategy for these lesions. This study aimed to evaluate the efficacy and safety of ESD for the treatment of rectal tumor extending to the dentate line.

Methods All consecutive rectal lesions submitted to ESD in our center, between January 2013 and October 2019, were enrolled. Time of procedure, rates of en bloc resection, R0 resection and curative resection, complications and tumor recurrence were analyzed, and a comparative analyses was carried out between lesions involving the dentate line (DL) and not involving the dentate line (NDL).

Results 149 rectal lesions were included: 39 in the DL group (26%) and 110 in the NDL group (74%). Median procedure time was comparable between groups (DL 78 vs NDL 75 min, p=0.959). No significant difference among the groups was found in the en bloc resection rate (DL 97% vs NDL 93%, p=0.447), R0 resection rate (DL 69% vs NDL 79%, p=0.202) or curative resection rate (DL 64% vs NDL 77%, p=0.139). Incidence of complications was similar (DL 10% vs NDL 11%, p=1) and none required surgery. During follow-up, recurrence was observed in 3 patients (2 in the DL group and 1 in the NDL group) and was treated endoscopically.

Conclusions ESD is an effective and safe treatment for rectal tumor extending to the dentate line, with similar outcomes compared to ESD in other rectal areas, when performed by experienced endoscopists. Therefore, it should be considered in the management of these lesions.