No need to stay above the line: anorectal junction endoscopic submucosal dissection is comparable to other rectal locations

Aims Evaluate the outcomes of rectal ESD and compare the resection of anorectal junction (ARJ) lesions with more proximal rectal (MPR) lesions, regarding feasibility, safety and efficacy.

Methods Retrospective unicentric study including consecutive patients submitted to rectal ESD. ARJ lesions were considered as those totally or partially located within 2 cm of the dentate line. ESD failure was determined whenever the target lesion was not removed. En bloc resection required that the target lesion be retrieved in one single specimen. R0 resection was achieved when pathological evaluation showed free horizontal and vertical margins in an en bloc resected specimen. Specimens with thermal effects at the margins preventing the pathologist from excluding abnormal cells were considered R1. Curative resection was considered low- (LGD) or high-grade dysplasia (HGD) with R0 resection or lesions harboring a well-differentiated adenocarcinoma with superficial submucosal invasion (< 1mm), with negative margins (> 1mm), without lymphatic/vascular invasion or tumor budding.

Results A total of 26 patients were included, 12 (46.2%) had an ARJ lesion and 14 (53.8%) had a MPR lesion. Most lesions were Paris 0-IIa+Is (61.5%), followed by 0-IIa+b (15.4%). Technical success was achieved in 25 patients (96.2%), with no significant differences between those with an ARJ lesion and those with a MPR lesion (100.0% vs 92.9%, p=1.000). There were also no significant differences in the rate of en bloc resection (91.7% vs 92.9%, p=1.000). Most lesions harbored HGD (84.0%), with no significant differences in histology between ARJ and MPR lesions: in ARJ lesions, LGD occurred in 16.7% and HGD in 83.3% vs in MPR lesions, HGD in 84.6% and adenocarcinoma in 15.4% (p=0.134). The global R0 resection rate was 61.5% and curative rate was 57.7%, both without statistically significant differences between patients with ARJ lesions and MPR lesions (50.0% vs 71.4%, p=0.422 and 50.0% vs 64.3%, p=0.462). Regarding complications, there were no significant differences between patients with ARJ lesions and MPR lesions in the rate of significant intraprocedural bleeding (41.7% vs 35.7%, p=1.000) and exposure/section of muscular fibers with the need of closure of the eschar (8.3% vs 14.3%, p=1.000). The rate of postprocedural bacterial translocation and delayed bleeding were also similar between both groups (16.7% vs 21.4%, p=1.000 and 8.3% vs 7.1%, p=1.000, respectively). Only one (3.8%) patient needed surgery due to a non-curative ESD, with no residual disease in the surgical specimen. Seventeen patients (65.4%) underwent a surveillance colonoscopy 6 and 12 months after the ESD, with one (5.9%) patient having residual tissue at 6 months with LGD and none with residual tissue at 12 months.

Conclusions ESD of rectal lesions in the ARJ is a feasible and safe procedure, with technical success and en bloc resection rate similar to MPR lesions, without differences in complication rates.

Publication History

Article published online:
27 March 2025