The efficacy and safety of cold snare polypectomy in intermediate nonpedunculated polyps

Cold snare polypectomy (CSP) is increasingly popular because of its safety and convenience, but it is currently recognized as the best way to remove diminutive polyps (≤ 5 mm). CSP for nonpedunculated polyps ≥ 10 mm in size has not been well examined. We evaluate the safety and efficacy of CSP for benign-looking intermediate nonpedunculated polyps.

We reviewed intermediate nonpedunculated polyps that resected by CSP from 2021 to 2023. The lesions were carefully observed with high-definition white-light (HD-WL) endoscopy and magnifying endoscopy with narrow-band imaging (ME-NBI) before CSP. We analyzed lesion characteristics, complete resection, cold snare defect protrusion (CSDP), histopathology, adverse events, and recurrence/residual. We compared the differences between lesions 10-14 mm in size and lesions ≥ 15 mm in size. We also analyzed risk factors for recurrence/residual and incomplete resection.

We retrospectively analyzed 631 lesions in 482 patients. The average size was 11.1 ± 1.3 mm, of which 3.3% were ≥ 15 mm. The CSDP rate was 34.1%. The rates of post-polypectomy bleeding (PPB), delayed post-polypectomy bleeding (DPPB), post-polypectomy perforation (PPP) and delayed post-polypectomy perforation (DPPP) were 0.3%, 0.2%, 0.0% and 0.0%, respectively. Two lesions were carcinoma in situ (0.3%) and seven lesions were high-grade dysplasia (HGD) (1.1%). The histological complete resection rate (the horizontal margin) was 94.3%. There were significant differences in sex, histological complete resection rate, and CSDP rate between lesions 10-14 mm in size and lesions ≥ 15 mm in size. CSDP was the only risk factor for incomplete resection of the polyps.

CSP of intermediate nonpedunculated polyps is safe and effective. The recurrence/residual rate and the adverse event rate were low.