Smith, Zachary L.

Background Complications of endoscopic mucosal resection (EMR) of large colorectal polyps remain a concern. Objective We aimed to compare safety and efficacy of cold EMR (without electrocautery) to hot EMR (with electrocautery) of large colorectal polyps. Design In this multicentre randomised trial, patients with any large (≥20 mm) non-pedunculated colon polyp were assigned to cold or hot EMR (primary intervention), and to submucosal injection with a viscous or non-viscous solution (secondary intervention) following a 2×2 design. The primary outcome was the rate of severe adverse events (SAEs). The secondary outcome was polyp recurrence. In this study, we report results of the primary intervention. Results 660 patients were randomised and analysed. An SAE was observed in 2.1% of patients in the cold EMR group and in 4.3% in the hot EMR group (p=0.10) (per protocol analysis 1.4 vs 5.0%, p=0.017) with fewer perforations following cold EMR (0%) compared with hot EMR (1.6%, p=0.028). Postprocedure bleeding did not differ (1.5% vs 2.2%, p=0.57). The effect of cold resection was independent of the type of submucosal injection solution, polyp size or antithrombotic medications. Recurrence was detected in 27.6% and 13.6% in the cold and hot EMR groups, respectively (p<0.001). Recurrence was not significantly different for 20–29 mm polyps (18.6% vs 13.4%, p=0.24) and for sessile serrated polyps (14.1% vs 8.5%, p=0.33). Conclusion Universal application of cold EMR did not significantly lower SAEs (unless cold EMR could be completed) and doubled the recurrence rate compared with hot EMR. Trial registration details ClinicalTrials.gov, number: NCT03865537 .

INTRODUCTION: Prophylactic pancreatic stent placement (PSP) is effective for preventing pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP) in high-risk cases, but the optimal technical approach to this intervention remains uncertain. METHODS: In this secondary analysis of 787 clinical trial patients who underwent successful stent placement, we studied the impact of (i) whether pancreatic wire access was achieved for the sole purpose of PSP or naturally during the conduct of the case, (ii) the amount of effort expended on PSP, (iii) stent length, (iv) stent diameter, and (v) guidewire caliber. We used logistic regression models to examine the adjusted association between each technical factor and post-ERCP pancreatitis (PEP). RESULTS: Ninety-one of the 787 patients experienced PEP. There was no clear association between PEP and whether pancreatic wire access was achieved for the sole purpose of PSP (vs occurring naturally; odds ratio [OR] 0.82, 95% confidence interval [CI] 0.37–1.84), whether substantial effort expended on stent placement (vs nonsubstantial effort; OR 1.58, 95% CI 0.73–3.45), stent length (>5 vs ≤5 cm; OR 1.01, 95% CI 0.63–1.61), stent diameter (≥5 vs <5 Fr; OR 1.13, 95% CI 0.65–1.96), or guidewire caliber (0.035 vs 0.025 in; 0.83, 95% CI 0.49–1.41). DISCUSSION: The 5 modifiable technical factors studied in this secondary analysis of large-scale randomized trial data did not appear to have a strong impact on the benefit of prophylactic PSP in preventing PEP after high-risk ERCP. Within the limitations of post hoc subgroup analysis, these findings may have important implications in procedural decision making and suggest that the benefit of PSP is robust to variations in technical approach.