Background: The diagnosis of Barrett's esophagus (BE) requires histologic confirmation of specialized intestinal metaplasia (SIM) through biopsy, a technique prone to sampling error. One method designed to improve the yield of biopsy uses acetic acid with magnification endoscopy: enhanced magnification endoscopy (EME). This technique identifies several mucosal surface patterns, and of these, pattern types III and IV have been associated with SIM.
Methods: We conducted a prospective, randomized trial to compare EME-directed biopsies and standard endoscopy with random biopsies in patients with symptoms of gastroesophageal reflux disease. Patients in the standard endoscopy group with evidence of BE had four-quadrant random biopsies taken every 2 cm. If there was no BE, four-quadrant biopsies were taken at the SCJ. Patients in the EME group had the mucosa at the SCJ classified as type I-IV based on published criteria. Biopsies targeted to type III and IV were compared to random biopsies.
Results: One hundred thirty-seven patients enrolled (68 randomized to EME, 69 to standard endoscopy). Fifty-six (41%) had endoscopic evidence of BE (20 standard endoscopy [29%] vs 36 EME [53%]). Of the patients with apparent BE, standard endoscopy with random biopsies confirmed SIM in 12 (60%) compared to 11 of 18 (61%) patients with EME targeted biopsies of patterns type III or IV (p = 1.0). Patients without apparent BE (N = 81) had SIM of the SCJ confirmed in 16% (8 of 49) with standard endoscopy and random biopsies compared with 8% (1 of 12) using EME-directed biopsy of pattern III or IV (p = 0.67).
Conclusions: Random biopsies of endoscopically apparent BE and a normal SCJ yield SIM at the same rate as targeted biopsies with EME in patients with pattern types III or IV. This calls into question the utility of this technique in reducing sampling error to identify SIM.