Background: Narrow band imaging (NBI) can accurately discriminate gastritis but premalignant lesions (PMLs) are difficult to detect.
Aims: The purpose of this study was to compare white light endoscopy (WLE) and histopathologic findings using the updated Sydney protocol (USP) with NBI and targeted biopsies (TB).
Methods: One hundred nineteen symptomatic patients referred for upper GI endoscopy were included in this prospective open study. All patients were assessed for gastritis and PMLs using WLE and NBI by two endoscopists selected in a random manner. Biopsies were taken according to USP and targeted from any area suspicious for PML. Imaging and histological findings between protocols were compared.
Results: In total 45 patients (38 %) had atrophy of whom 39 (32.7 %) were detected with WLE-USP and 28 (23.5 %) with NBI-TB (p = 0.03), 25 (21 %) had intestinal metaplasia (IM) of whom 19 (16 %) were detected with WLE-USP and 18 (15.1 %) with NBI-TB (p = 0.7) and 14 (12 %) had dysplasia of whom 12 (10 %) were detected with WLE-USP and 7 (7 %) with NBI-TB (p = 0.5), and 1 (0.8 %) case of gastric cancer only detected with WLE-USP. Accuracies for atrophy and IM were 93 and 90 % for the WLE-USP and 80 and 82 % for NBI-TB. The NBI-TB detected six cases of atrophy (13 %), 5 (20 %) of IM, and 2 (14 %) of dysplasia missed by WLE-USP as agreement was moderate. Accuracies of the NBI patterns for body and antral gastritis were 80 and 84 %.
Conclusions: In a non high-risk population NBI-TB has less accuracy in detecting premalignant lesions compared to WLE-USP. However, it may be used as an important and easy-to-use complementary method which increases overall detectability for gastric premalignant lesions.