Efficacy and safety of cold vs hot snare polypectomy for small (5-9 mm) colorectal polyps: a multicenter randomized controlled trial.

Background and aims: Currently available resection techniques for small polyps include cold snare polypectomy (CSP) and hot snare polypectomy (HSP). We aimed to compare CSP vs HSP in 5-9 mm polyps in terms of complete resection and adverse events rates. Methods: Multicenter, randomized trial conducted in 7 Spanish centers between February-November 2019. Patients with ≥1 5-9mm polyp were randomized to CSP or HSP, regardless of morphology or pit pattern. After polyp removal, two marginal biopsies were submitted to a single pathologist blind to polyp histology. Complete resection was defined as the only finding of normal mucosa or burn artifacts in the biopsies. Abdominal pain was only assessed in patients without 9mm polyps. Results: A total of 496 subjects were randomized; 237 (394 polyps) to CSP and 259 (397 polyps) to HSP. Complete polypectomy rates were 92.5% with CSP and 94% with HSP (difference 1.5%, 95%CI: 4.9% to -1.9%). Intraprocedural bleeding appeared in 3 (0.8%) CSPs and 7 (1.8%) HSPs (p=0.34). One (0.3%) lesion per group presented delayed hemorrhage. Post-colonoscopy abdominal pain presented similarly in both groups 1 hour after the procedure (18.8% in CSP vs 18.4% in HSP), but, after 5 hours, it was higher in HSP group (5.9% vs 16,5%, p=0.02). CSP presented a higher proportion of asymptomatic patients 24h after the procedure than HSP, 97% vs 86.4% (p=0.01). Conclusions: We observed no differences in complete resection and bleeding rates between CSP and HSP. CSP reduces the intensity and duration of post-colonoscopy abdominal pain (ClinicalTrials.gov number: NCT03783156).