Comparison of probe-based confocal endomicroscopy with virtual chromoendoscopy and white-light endoscopy for diagnosis of gastric intestinal metaplasia

Abstract

We prospectively compared the diagnostic performance of autofluorescence imaging (AFI), magnifying narrow band imaging (mNBI), and probe-based confocal laser endomicroscopy (pCLE) with white light endoscopy (WLE) for the diagnosis of gastric intestinal metaplasia (GIM), using histology as the "gold standard." Chinese >50 years old with history of GIM were prospectively recruited. All subjects underwent WLE, followed by AFI and NBI, and finally pCLE. Patients were randomized to undergo either AFI before NBI or vice versa. In each patient, a minimum of six sites (antrum lesser and greater curve, body lesser and greater curve, incisura, cardia, and any lesion) were each examined by WLE, AFI, NBI, and pCLE. The diagnoses were made real-time. Biopsies for histology were taken from all examined sites. pCLE videos also were reviewed off-site. Analysis was performed per-site. A total of 125 sites in 20 patients were examined. For diagnosing GIM, real-time pCLE had better sensitivity (90.9 vs. 37.9%, p < 0.001) and accuracy (88.0 vs. 64.8%, p < 0.001) compared with WLE. Sensitivity (90.9 vs. 68.2%, p = 0.001), specificity (84.7 vs. 69.5%, p = 0.042), and accuracy (88 vs. 68.8%, p < 0.001) of real-time pCLE were better than AFI. Sensitivity, specificity, and accuracy of real-time pCLE and mNBI for diagnosing GIM were similar. Off-site pCLE had significantly better accuracy for diagnosing GIM compared to WLE, AFI, and mNBI. Off-site pCLE had superior specificity (94.9 vs. 84.7%, p = 0.031) and accuracy (95.2 vs. 88.0%, p = 0.012) compared with real-time pCLE. pCLE was superior to AFI and WLE for diagnosing GIM. Off-site review improved performance of pCLE.