Incomplete resection rates of 4- to 20-mm non-pedunculated colorectal polyps when using wide-field cold snare resection with routine submucosal injection.

Background and study aims Incomplete resection of 4- to 20-mm colorectal polyps occur frequently (> 10 %), putting patients at risk for post-colonoscopy colorectal cancer. We hypothesized that routine use of wide-field cold snare resection with submucosal injection (CSP-SI) might reduce incomplete resection rates (IRRs). Patients and methods Patients aged 45 to 80 years undergoing elective colonoscopies were enrolled in a prospective clinical study. All 4- to 20-mm non-pedunculated polyps were resected using CSP-SI. Post-polypectomy margin biopsies were obtained to determine IRRs through histopathology assessment. The primary outcome was IRR, defined as remnant polyp tissue found on margin biopsies. Secondary outcomes included technical success and complication rates. Results A total of 429 patients (median age 65 years, 47.1 % female, adenoma detection rate 40 %) with 204 non-pedunculated colorectal polyps 4 to 20 mm removed using CSP-SI were included in the final analysis. CSP-SI was technical successful in 97.5 % (199/204) of cases (5 conversion to hot snare polypectomy). IRR for CSP-SI was 3.8 % (7/183) (95 % confidence interval [CI] 2.7 %-5.5 %). IRR was 1.6 % (2/129), 16 % (4/25), and 3.4 % (1/29) for adenomas, serrated lesions, and hyperplastic polyps respectively. IRR was 2.3 % (2/87), 6.3 % (4/64), 4.0 % (6/151), and 3.1 % (1/32) for polyps 4 to 5 mm, 6 to 9 mm, < 10 mm, and 10 to 20 mm, respectively. There were no CSP-SI-related serious adverse events. Conclusions Use of CSP-SI results in lower IRRs compared to what has previously been reported in the literature for hot or cold snare polypectomy when not using wide-field cold snare resection with submucosal injection. CSP-SI showed an excellent safety and efficacy profile, however comparative studies to CSP without SI are required to confirm these results.

EMR combined with hybrid argon plasma coagulation to prevent recurrence of large nonpedunculated colorectal polyps (with videos).

BACKGROUND AND AIMS: EMR is the mainstay of therapy for large colorectal polyps. Local recurrence after EMR is common and can be reduced using margin ablation. Our aim was to evaluate recurrence rates when using hybrid argon plasma coagulation (h-APC) ablation after EMR. METHODS: Adult patients (aged 18-89 years) undergoing EMR of nonpedunculated colorectal polyps ≥20 mm were enrolled in a prospective multicenter study. h-APC was used to ablate all defect margins and also the resection surface in selected cases. The primary study outcome was recurrence rates found during the first follow-up colonoscopy. Secondary outcomes were technical success and adverse event rates. RESULTS: EMR with h-APC ablation was used in 101 polyps (84 patients, 46.4% women). EMR with h-APC ablation was technically successful in all cases (median EMR time, 15 minutes; median h-APC ablation time, 4 minutes). Median polyp size was 30 mm (range, 20-60). Resected polyps were either adenomas (68/101 [67.3%]), sessile serrated lesions (27/101 [27%]), or adenocarcinomas (6/101 [6%]). The post-EMR recurrence rate was 2.2% (2/91) (95% confidence interval, .27-7.71). All 6 patients with cancer (intramucosal cancer, 4; T1sm cancer, 2) were found to have complete eradication of the primary tumor after EMR with h-APC, and none had lymph node metastasis. Four serious adverse events occurred in 3 patients (2 delayed bleeding [2.4%], 1 abdominal pain [1.2%], and 1 microperforation [1.2%]. All serious adverse events resolved with either endoscopic or antibiotic treatment only. CONCLUSIONS: EMR with h-APC showed a high technical success rate, low adverse event rate, and very low post-EMR recurrence rates. (Clinical trial registration number: NCT04015765.).