Background: There are few randomized studies examining efficacy of snares and agents in EMR. Objective: To compare the use of a combined needle and snare unit with injectate versus a spiral wire and injectate (primary);saline solution versus hydroxypropyl methylcellulose (secondary). Design: Prospective, randomized, factorial, single center. Setting: Tertiary-care academic medical center. Patients: A total of 140 patients with large (>15 mm), sessile, colorectal polyps. Interventions: Polyps randomized to either 1 of 2 snare types and 1 of 2 injectates. Main Outcome Measurements: Primary - the Sydney resection quotient (SRQ), defined as the size of the polyp divided by the number of pieces resected and the amount of tissue per snare attempt. Secondary - procedure time, adverse events, residual neoplasia at follow-up. Results: The SRQ was higher with thecombined unit (median 13.8 mm vs 7.1 mm; P = .019); additionally, procedure time was less (median 6 vs 11 minutes; P < .001). Resection was considered complete after the EMR in 62% (42/68) with the combined needle and snare unit versus 51% (37/72; P = .22) with the spiral wire. Rates of adverse events were similar. Residual neoplasia was found at follow-up in 22% (10/46) with thecombined needle and snare unit versus 21% (10/48; P = .89) with the spiral wire. There was no evidence of differences in outcomes by lifting agent. Limitations: The SRQ is only a surrogate marker. Conclusion: This study provides evidence that the integrated needle-snare may be superior to the snare alone for the removal of large, flat polyps. Additionally, the type of injectate appears to have no impact on outcome.
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging