Incomplete Resection of Colorectal Polyps: Data from a Systematic Review and Meta-Analysis

colon polyp
polyp, polypectomy, colonoscopy, colon polyp
Colorectal polyps that are 1-20 mm in size are frequently resected incompletely, according to recent study data.

Colorectal polyps that are 1-20 mm in size are frequently resected incompletely, according to study data published in Gastroenterology. In a meta-analysis conducted using data from over 9000 polypectomies, the incomplete resection rate (IRR) was 14% with snare removal. Incomplete resection was most commonly observed for polyps ≥10 mm. 

Researchers conducted a systematic search of MEDLINE, EMBASE, EBM Reviews, and CINAHL from inception through March 2019 for full-text articles reporting the IRRs of polyps 1–20 mm in size during screening, surveillance, or diagnostic colonoscopies. Exclusion criteria includes: patients with inflammatory bowel disease, referrals for difficult polypectomy, polyp size >20 mm, endoscopic submucosal dissection, and endoscopic mucosal resection for polyps >20 mm. A total of 2 independent researchers reviewed eligible articles. Disagreements regarding inclusion were resolved through consensus with a third researcher. Reviewers extracted study type, histology type, polyp resection method, and means of IRR assessment. The primary outcome was the IRR for snare removal of polyps 1-20 mm in size. Secondary outcomes included IRR for polyps 1-10 mm and 10-20 mm in size; IRR for hot and cold snare removal of polyps 1-10 mm and 10-20 mm; IRR for snare removal with or without submucosal injection; and IRR for forceps and cold snare removal of polyps 1-5 mm. Researchers used the Newcastle-Ottawa Scale and the Cochrane risk of bias tool to evaluate study quality and risk for bias, respectively.

Of 175 full-text articles reviewed for eligibility, researchers included 36 in the systematic review and meta-analysis. These studies comprised a total of 9282 resected polyps. Across all studies, researchers detected low risk for publication bias. Quality assessment indicated that 5 studies were of poor quality, while the rest were of good quality or higher. Overall, the IRR for snare removal of polyps 1-20 mm in size was 13.8% (95% CI, 10.3-17.3; 13 studies; 5128 polypectomies). When stratified by size, polyps ≥10 mm had a greater IRR with snare removal than polyps ≤10 mm (20.8% [95% CI, 12.9-28.8] vs 15.9% [95% CI, 9.6-22.1]).  For polyps ≤10 mm, snare IRR with submucosal injection was lower than snare IRR without submucosal injection (14.2% [95% CI, 5.2-23.2] vs 17.6% [95% CI, 13.1-22.1]). For polyps ≥10 mm, only 1 study did not perform submucosal injections during resection. For polyps 1-10 mm, the IRRs for hot snare removal and cold snare removal were comparable, at 14.2% (95% CI, 5.2-23.2) and 17.3% (95% CI, 14.3-20.3), respectively. For polyps ≥10 mm, the majority of studies performed hot snare polypectomy. For polyps ≤5 mm, snare removal was associated with significantly lower IRR than forceps removal (4.4% [2.9-6.1] vs 9.9% [7.1-13.0]).

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Based on this analysis of current literature, a significant proportion of 1-20 mm colorectal polyps are incompletely resected using snares. IRRs were particularly high for polyps ≥10 mm. For polyps ≤5 mm, snare removal appeared to outperform forceps removal. Study limitations include high heterogeneity of polyp assessment, polypectomy technique, and expert status of clinician performing the polypectomy. “Initiatives to implement completeness of polyp resection as an important colonoscopy quality metric…should be considered,” researchers wrote.

Disclosure: A study author declared affiliations with the pharmaceutical industry.

Please see the original reference for a full list of authors’ disclosures.

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Djinbachian R, Iratni R, Durand M, Marques P, von Renteln D. Rates of incomplete resection of 1-20mm colorectal polyps: a systematic review and meta-analysis [published online May 10, 2020]. Gastroenterology. doi: 10.1053/j.gastro.2020.05.018