Cap-Assisted vs Standard Endoscopic Mucosal Resection Superior for Removing Colorectal Tumors

Illustration of colorectal polyps, showing numerous polypous protrusions on the the lining of the intestine.
Researchers compared the feasibility and safety of cap-assisted and standard endoscopic mucosal resection for removing laterally spreading colorectal lesions.

Cap-assisted endoscopic mucosal resection (EMR-C) outperformed standard endoscopic mucosal resection (EMR-S) for removing laterally spreading colorectal lesions (LSTs), according to study results published in Gastrointestinal Endoscopy.

Researchers conducted a prospective randomized trial ( Identifier: NCT03498664) at 4 referral centers in Italy between 2018 and 2019. Adult patients (N=240) with colonic LSTs at least 30 mm in size were eligible for inclusion. Study participants were randomly assigned 1:1 to receive EMR-C (n=138) or EMR-S (n=102). In EMR-S, the lesion was surrounded by a mucosectomy snare and then resected. In EMR-C, a suction cap was preloaded onto the tip of the endoscopy scope; the lesion was suctioned into the cap and resected with a dedicated snare. After resection, patients underwent follow-up endoscopies at 3, 6, and 12 months. The primary outcomes were residual lesions and cancer recurrence rates at follow-up. Intraprocedural and postprocedural adverse events were also captured. 

A total of 143 and 102 lesions were resected in the EMR-C and EMR-S groups, respectively. Median lesion size was 30 (30-100) mm in the EMR-C group and 35 (30-60) mm in the EMR-S group. Median time required for the procedure was 20 (10-60) minutes for EMR-C and 30 (15-90) minutes for EMR-S (P <.001). Researchers used argon plasma coagulation as adjunctive treatment in 2.9% of EMR-C procedures, compared with 22.5% of EMR-S procedures (P <.001). The 12-month residual lesion rate was 31.4% in the EMR-S group and 5.8% in the EMR-C group (P <.001). Recurrence at 12 months was also greater in the EMR-S group vs EMR-C group (16.7% vs 5.1%; P <.001).

Adverse events occurred in 14 (10.1%) patients who underwent EMR-C and 22 (21.6%) patients who underwent EMR-S. Overall bleeding was recorded in 11 patients (8.0%) in the EMR-C group and 21 patients (20.6%) in the EMR-S group (P =.007). Intraprocedural adverse events occurred in 5 (3.5%) patients treated with EMR-C and 17 (16.7%) patients treated with EMR-S (P =.001).

Results from the study suggest that EMR-C is effective and feasible for the removal of large colorectal LSTs. Compared to standard EMR, EMR-C had a higher eradication rate, shorter resection time, lower risk for adverse events, and required less use of argon plasma coagulation.

Study limitations included enrolling a higher number of individuals for the EMR-C group, missing follow-up data after 12 months, and a lack of full participation in follow-up endoscopy among all patients.

“EMR-C should be performed by skilled endoscopists and the technique can be easily learned in specialized tertiary referral endoscopic units before its application in other centers,” the study authors wrote.


Conio M, Manta R, Filiberti RA, et al. Cap-assisted endoscopic mucosal resection versus standard inject and cut endoscopic mucosal resection for large colonic laterally spreading tumors treatment: a randomized multicenter study (with video). Gastrointest Endosc. Published online June 10, 2022. doi:10.1016/j.gie.2022.06.002