This recommendation holds up in the first randomized controlled trial of the practice.

Removal of small polyps during colonoscopic insertion might prevent colonoscopists from being unable to find them during withdrawal. This practice is commonly advocated by experts and considered standard practice by many colonoscopists. To evaluate whether this method actually results in fewer missed polyps compared with polypectomy during withdrawal only, investigators randomized 301 patients to undergo removal of polyps <1 cm in size during both colonoscopic insertion and withdrawal or during colonoscopic withdrawal only.

The number of polyps detected and removed did not differ between groups. In the group that underwent polypectomy during withdrawal only, 13 polyps (mean size, 3.15 mm) were seen during insertion but not during subsequent withdrawal, which represented 3.3% of all polyps removed in that group. The number of polyps considered technically difficult to remove and the duration of colonoscopy were similar between groups.

Citation(s):

Wildi SM et al. Colorectal polypectomy during insertion and withdrawal or only during withdrawal? A randomized controlled trial. Endoscopy 2012 Nov; 44:1019.