Risk factors for conversion to snare resection during colorectal endoscopic submucosal dissection in an expert Western center.

ABSTRACT

BACKGROUND: There are limited data regarding the risk factors and consequences of conversion to endoscopic mucosal resection (rescue EMR) during colorectal endoscopic submucosal dissection (ESD) in Western centers. METHODS: This was a retrospective analysis of a prospectively collected database, from which 225 consecutive ESDs performed between 2013 and 2017 were selected. Of the included patients, 39 (18.6 %) required rescue EMR. Pre- and per-procedure characteristics were evaluated to determine the features associated with the need for rescue EMR. Outcomes and complications were also assessed. RESULTS: 210 patients were included, with median tumor size of 40 mm (range 20 - 110) and most tumors being in a non-rectal location (66.2 %). When compared with full ESD, rescue EMR was significantly associated with lower rates of en bloc resection (43.6 % vs. 100 %) and complete resection (R0 status; 28.2 % vs. 88.9 %), and with a higher rate of recurrence (5.1 % vs. 0 %) and more need for surgery (15.4 % vs. 3.5 %). In multivariable analysis, non-lifting (adjusted odds ratio [ORa] 3.06, 95 % confidence interval [CI] 1.23 - 7.66; P = 0.02), nongranular-type laterally spreading tumor (LST-NG; ORa 2.56, 95 %CI 1.10 - 5.99; P = 0.03), and difficult retroflexion (OR 3.22, 95 %CI 1.01 - 10.28; P = 0.049) were independent risk factors associated with conversion to rescue EMR, while tumor size and location were not. CONCLUSIONS: During ESD, the presence of poor lifting, LST-NG morphology, and a difficult retroflexed approach were factors associated with the need to convert to rescue EMR. Conversion to rescue EMR remains a valuable strategy.