Resect and discard strategy in clinical practice: a prospective cohort study

Background and study aims: Narrow-band imaging (NBI) has shown promising results in discriminating adenomatous from non-adenomatous colonic polyps. In patients with small polyps (< 10 mm), the application of NBI within a “resect and discard” strategy, might allow post-polypectomy surveillance intervals to be determined independently from histopathology. The aim of the present study was to assess the feasibility and safety of this approach in routine clinical practice.

Patients and methods: Consecutive colonoscopy outpatients with one or more polyps smaller than 10 mm were prospectively included. Each polyp was categorized by the endoscopist as adenoma or non-adenoma according to simplified NBI criteria, and future post-polypectomy surveillance interval was assigned accordingly. Following histopathology, post-polypectomy surveillance interval was subsequently re-assigned, and the accordance between endoscopy- and histology-directed surveillance strategies was calculated.

Results: Among 942 colonoscopy patients, 286 (30.4 %) with only small polyps were included. In total, 511 small polyps were evaluated; 350 (68.5 %) were adenomas and 18 of these (5.1 %) had histologic features of advanced neoplasia. For the in vivo diagnosis of adenoma, NBI sensitivity, specificity, accuracy, and positive and negative likelihood ratios were 94.9 %, 65.8 %, 85.7 %, 2.80, and 0.08, respectively. The endoscopy-directed surveillance strategy was in accordance with the histology-directed strategy in 237 of 286 patients (82.9 %). In 9.8 % and 7.3 % patients, the endoscopy-directed approach would have resulted in early and delayed surveillance, respectively.

Conclusions: The resect and discard strategy seems to be a viable, safe, and cost-effective approach for the management of patients with small polyps. However, caution in the application of the strategy should be advocated for patients with polyps 6 – 9 mm in size and those with right-sided lesions, due to their malignant potential.

The study was registered on Clinicaltrials.gov (NCT01462123).

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