Determining the adenoma detection rate and adenomas per colonoscopy by photography alone: proof-of-concept study

Background and study aims: The adenoma detection rate (ADR) and adenomas detected per colonoscopy (APC) are measures of the quality of mucosal inspection during colonoscopy. In a resect and discard policy, pathologic assessment for calculation of ADR and APC would not be available. The aim of this study was to determine whether ADR and APC calculation based on photography alone is adequate compared with the pathology-based gold standard.

Patients and methods: A prospective, observational, proof-of-concept study was performed in an academic endoscopy unit. High definition photographs of consecutive polyps were taken, and pathology was estimated by the colonoscopist. Among 121 consecutive patients aged ≥ 50 years who underwent colonoscopy, 268 polyps were removed from 97 patients. Photographs of consecutive polyps were reviewed by a second endoscopist.

Results: The resect and discard policy applied to lesions that were ≤ 5 mm in size. When only photographs of lesions that were ultimately proven to be adenomas were included, the reviewer assessed ADR and APC to be lower than that determined by pathology (absolute reductions of 6.6 % and 0.17, and relative reductions of 12.6 % and 13.1 % in ADR and APC, respectively). When all photographs were included for calculation of ADR and APC, the reviewer determined the ADR to be 3.3 % lower (absolute reduction) and the APC to be the same as the rates determined by pathology.

Conclusions: In a simulated resect and discard strategy, a high-level detector can document adequate ADR and APC by photography alone.

• References

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