How Does CS-EMR Fare for Nonampullary Duodenal Adenoma Removal?

Cold snare endoscopic mucosal resection is safe and efficacious for nonampullary duodenal adenoma removal.

Cold snare endoscopic mucosal resection (CS-EMR) is a safe and efficacious method for removal of nonampullary duodenal adenomas and has an acceptable recurrence rate, according to a study in the Journal of Clinical Gastroenterology.

The systematic review and meta-analysis included a search of the PubMed, EMBASE, Cochrane,, Web of Science, and SCOPUS databases from inception to February 2023.

Eligible studies reported use of cold EMR, included duodenal lesions, and had a minimum of 10 patients. The primary analysis was calculating the pooled technical success rates and polyp recurrence rates.

The meta-analysis included 6 studies with 333 patients — 2 studies from the United States, 3 from Australia, and 1 multicenter study. CS-EMR was used to resect 178 duodenal polyps.

Randomized controlled studies are needed to compare conventional EMR, CS-EMR, and underwater EMR for large duodenal adenomas.

The overall pooled technical success rate was 95.8% (95% CI, 89.1%-98.5%; I2=21.5%). Based on 4 studies, the pooled technical success for polyps of at least 1 cm was 96.1% (95% CI, 84.8%-99.1%; I2=44%). Follow-up data were available for 4 studies, which showed a pooled recurrence rate of 21.2% (95% CI, 8.5%-43.6%; I2=78%). The pooled rate of recurrence for polyps of at least 1 cm from 3 studies was 26.5% (95% CI, 11.8%-49.2%; I2=79%).

Among safety outcomes, the pooled rates were 4.2% for immediate bleeding (95% CI, 1.6%-10.5%; I2=12%), 3.4% for delayed bleeding (95% CI, 1.5%-7.6%; I2=0%), 2.8% for perforation (95% CI, 1.1%-6.7%; I2=0%), and 2% for postpolypectomy syndrome (95% CI, 0.5%-7.5%; I2=0%). No patients died.

Conventional EMR data were obtained from 3 studies with 165 patients/polyps. The pooled technical success rate was 95.1% (95% CI, 80%-98.9%; I2=47.7%). Polyp recurrence was reported in 2 studies, with a pooled recurrence rate of 22% (95% CI, 15.8%-29.7%; I2=0%). For adverse events, the pooled rates were 11.8% (95% CI, 7.3%-18.8%; I2=0%) for immediate bleeding, 15.3% (95% CI, 10.5%-21.7%; I2=0%) for delayed bleeding, and 7.2% (95% CI, 3.4%-14.7%; I2=16.6%) for perforation.

An exploratory analysis that compared CS-EMR with conventional EMR demonstrated a significantly lower rate of delayed bleeding with CS-EMR (2%, CI 0.4%-9.3%; I2=0%) (odds ratio, 0.11; 95% CI, 0.02-0.62; P =.012; I2=0%).

The study was limited by the inclusion of only data from observational studies, and expert endoscopists performed CS-EMR in a majority of the studies. Also, the results are exploratory, as the primary studies were not controlled. Furthermore, the investigators were unable to pool the efficacy and safety outcomes according to lesion size.

“Based on these meta-analysis results, CS-EMR is an effective and safe technique for removing nonampullary duodenal adenomas,” researchers noted. “Randomized controlled studies are needed to compare conventional EMR, CS-EMR, and underwater EMR for large duodenal adenomas.”


Mohamed MFH, Ahmed K, Rajadurai S, et al. Efficacy and safety of cold snare endoscopic mucosal resection (CS-EMR) for nonampullary duodenal polyps: systematic review and meta-analysis. J Clin Gastroenterol. Published online August 7, 2023. doi:10.1097/MCG.0000000000001898