Background and study aims: Distinguishing sessile serrated adenomas/polyps (SSA/Ps) from non-neoplastic tissue
may be challenging when white-light endoscopy (WLE) is used. Image-enhanced endoscopy
(IEE) has shown accuracy in differentiating adenomas from hyperplastic polyps. The
aim of this systematic review and meta-analysis was to evaluate the utility of IEE
in diagnosis of SSA/Ps.
Methods: Studies were eligible if: they included patients undergoing colonoscopy with an endoscopy-based
image-enhancement modality; endoscopic diagnoses, including SSA/P, were based on the
appearance of polyps at IEE; and the corresponding histologic diagnoses of polyps
were provided. The primary outcome was sensitivity of IEE for SSA/Ps differentiated
from non-neoplastic lesions (primary convention) and differentiated from all non-SSA/P
lesions, including adenomas (secondary convention).
Results: 13 studies met inclusion criteria. Sensitivity ranged from 38 % to 100 % but sensitivity ≥ 90 %
was seen in 4 of 10 narrow band imaging (NBI) or magnification-NBI studies. Pooled
sensitivities for discriminating SSA/Ps from non-neoplastic lesions were 80 % for
magnification-NBI, 60 % for NBI, 49 % for autofluorescence, and 47 % for flexible
spectral imaging color enhancement. In head-to-head comparisons with WLE, NBI (89 %
vs. 75 %) and magnification-NBI (78 % vs. 63 %) demonstrated significantly greater
sensitivity, while autofluorescence imaging (56 % vs. 66 %), flexible spectral imaging
color enhancement (100 % vs. 100 %), and high-resolution endomicroscopy (88 % vs.
100 %) did not.
Conclusion: IEE currently cannot be recommended as a diagnostic tool for SSA/P. While NBI studies
showed promise, more IEE studies employing validated SSA/P criteria in well-defined
polyp populations are needed. IEE studies assessing SSA/P detection rates at colonoscopy
are also needed.