Acetic acid–guided biopsies after magnifying endoscopy compared with random biopsies in the detection of Barrett's esophagus: a prospective randomized trial with crossover design

Background In contrast to standard video endoscopy, magnifying endoscopy after local acetic acid application enables recognition of mucosal surface architecture. Objective To investigate the diagnostic yield of magnifying endoscopy with acetic acid–targeted biopsies compared to random, 4-quadrant biopsies. Design Prospective randomized trial (ratio 1:1) with crossover design. Setting Two referral hospitals in Germany. Patients Thirty-one patients with Barrett's esophagus or visible columnar-lined lower esophagus. Interventions Patients were randomized to undergo either standard video endoscopy with 4-quadrant biopsies or magnifying endoscopy in conjunction with acetic acid application. All patients were re-examined 14 days after the initial endoscopy with the corresponding procedure. Main Outcome Measurements Primary outcome analysis (per protocol and per biopsy) was the histological proof of Barrett's epithelium. Secondary outcome analysis was the correlation between the surface architecture and the presence of Barrett's epithelium and the needed number of biopsies to confirm Barrett's epithelium for the 2 different procedures. Results Magnifying endoscopy enabled the prediction of Barrett's epithelium with a sensitivity of 100% and a specificity of 66%, respectively (accuracy 83.8%). Acetic acid–guided biopsies obtained a significantly higher percentage of tissues containing SCE (78%; 188/241) compared to random biopsies (57%; 159/280). Limitations No data on the diagnosis of Barrett's dysplasia. Conclusion Magnifying endoscopy with acetic acid–guided biopsies is superior to standard video endoscopy with random biopsies, and the number of biopsies needed to confirm Barrett's epithelium is half as much when compared to random biopsies.