Cold Snare Polypectomy Failed for 10- to 20-mm Colorectal Polyps
Douglas K. Rex, MD, MASGE, reviewing von Renteln D, et al. Endoscopy 2022 Nov 14.
Cold snare is now considered the polypectomy method of choice for polyps <10 mm in size, and recent studies have extended the use of cold polypectomy to some lesions ≥10 mm in size.
In the current study, 142 lesions 4 to 9 mm in size and 40 lesions 10 to 20 mm in size were removed by cold snare polypectomy. After resection, 2 biopsy samples were taken from the resection margin of the 4- to 9-mm lesions, and 4 quadrant biopsy specimens were obtained from the resection margin defect for 10- to 20-mm lesions.
Conversion to hot snare resection was required in less than 1% of 4- to 9-mm lesions but was necessary in 44% of the 10- to 20-mm lesions. Visible residual polyp was seen after „initial“ resection in 13% of 4- to 9-mm lesions and 18% of 10- to 20-mm lesions. Of the lesions removed by a cold snare without conversion to a hot snare, 19% had incomplete resection, as judged by margin biopsy, without much difference between size categories.
The overall rate of incomplete resection was 26% for serrated lesions, but the difference was not significant. Incomplete resection was associated with flat lesions (odds ratio [OR], 2.9), resection judged as difficult (OR, 4.2), piecemeal resection (OR, 6.6), and visible polyp after „initial” resection (OR, 5.4). Among endoscopists with ≥10 resections, the rate of incomplete resection ranged from 8% to 33%. Overall, 63% of 10- to 20-mm polyps had either incomplete resection or required conversion to hot snaring. Neither use of dedicated snares nor submucosal injection affected complete resection rates.
COMMENTThe rates of incomplete resection and failure to complete resection of 10- to 20-mm polyps with cold techniques are surprisingly high, given the optical capacity of current colonoscopes and the extensive experience available in cold snaring. This study might be an outlier, given the results of some recent trials, but does indicate that individual endoscopists still struggle with cold snare technique, and additional efforts to standardize cold snare technique and teach it effectively are needed.
Note to readers: At the time we reviewed this paper, its publisher noted that it was not in final form and that subsequent changes might be made.
CITATION(S)
von Renteln D, Djinbachian R, Benard F, et al. Incomplete resection of 4-20 mm colorectal polyps when using cold snare and associated factors. Endoscopy 2022 Nov 14. (Epub ahead of print) (https://doi.org/10.1055/a-1978-3277)
