Methods: Patients undergoing surveillance endoscopy for BE were invited to participate. The BE segment was initially evaluated with NBI overview (NBI-O) as a ‘red flag’ technique. Abnormal areas identified with NBI-O were then further interrogated with NBI and a dual focus magnification system (NBI-DF) in order to aid characterization. Normal areas on NBI-O were also systematically assessed with NBI-DF (four quadrants every 2 cm). In addition, a confidence system was utilized when each area was assessed with NBI-DF. All areas

on NBI-DF were classified according to a simplified classification system into 3 distinguishable mucosal patterns: (i) regular pits with regular microvasculature (no dysplasia)- high confidence; (ii) irregular pits with irregular PLX4032 ic50 microvasculature (early cancer/high-grade dysplasia [HGD])-high confidence; and (iii) equivocal, where the endoscopist was not sure about the pattern (i.e. areas with increased Selleck Palbociclib brownish discoloration on NBI-O and dilated vasculature but no change in calibre on NBI-DF [likely inflammation or low-grade dysplasia: LGD])- low confidence. Corresponding biopsies of each area were then taken.

The sensitivity (Sn), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) of both modes (NBI overview and NBI-DF) were then compared with the final histopathological diagnosis. Results: Two hundred and twenty-one areas in 40 patients with BE were

examined prospectively. One hundred and Selleck Baf-A1 eighty-three of 221 areas (82.8%) did not exhibit any dysplasia on final histopathological assessment. NBI-O and NBI-DF accurately called all these areas as non-dysplastic. The 38 areas that appeared suspicious on NBI-O were further assessed with NBI-DF: 7 of 7 areas were accurately predicted as harbouring no dysplasia and 9 areas were predicted as irregular, of which 4 harboured early cancer, 1 HGD, 3 LGD and 1 inflammation on final histopathology assessment. The remaining 22 areas were deemed to be equivocal (final histopathology: 18 LGD and 4 inflammation). The Sn, Sp, PPV and NPV for the prediction of dysplasia/early cancer using NBI-O and NBI-DF were thus 100%, 93.8%, 68.6%, 100% and 100%, 86.2%, 73.3%, 100%, respectively. Conclusion: If NBI-DF was used as a characterisation tool on abnormal areas picked up by NBI-O, biopsies would have been avoided in 190 of 221 areas (86%). In addition, all areas harbouring early cancer and HGD could be accurately identified. We propose a paradigm shift on how patients with BE could be surveyed where high confidence areas could be left alone or subjected to an endoscopic resection (regular or irregular morphology on NBI-DF respectively) whilst low confidence regions (equivocal) biopsied.