The impact of submucosal fatty tissue during colon endoscopic submucosal dissection in a western center

Obesity is associated with submucosal fatty tissue. The main aim of this study was to assess the impact of submucosal fatty tissue on the success of colonic endoscopic submucosal dissection (C-ESD) in a western population.

This was a retrospective analysis of 125 consecutive C-ESDs performed between October 2015 and July 2017. Fatty tissue sign was defined as positive when the submucosal layer was covered with fatty tissue. The complexity of performing an ESD was assessed by the performing endoscopist, defined by the occurrence of intraprocedural perforation, inability to complete an en-bloc resection or a procedure time exceeding 180 min.

Fatty tissue sign positive was present in 44.8% of the procedures. There were 28 (22.4%) c-ESD defined as complex. Factors associated with complex ESD included; fatty tissue sign [odds ratio (OR) 12.5; 95% confidence interval (CI), 1.9-81.9; P = 0.008], severe fibrosis (OR 148.6; 95% CI, 6.6-3358.0; P = 0.002), poor maneuverability (OR 267.4; 95% CI, 11.5-6212.5; P < 0.001) and polyp size ≥35 mm (OR 17.2; 95% CI, 2.6-113.8; P = 0.003). In patients demonstrating the fatty tissue sign, BMI and waist-to-height ratio (WHtR) were higher (27.8 vs. 24.7; P < 0.001 and 0.56 vs. 0.49; P < 0.001, respectively) and en-bloc resection was achieved less frequently (76.8 vs. 97.1%, P = 0.001). Multivariate analysis revealed higher risk of fatty tissue sign positive associated with WHtR ≥0.52 (OR 26.10, 95% CI, 7.63-89.35, P < 0.001).

This study demonstrates that the fatty tissue sign contributes to procedural complexity during C-ESD. Central obesity correlates with the likelihood of submucosal fatty tissue and as such should be taken into account when planning procedures.