Real-time diagnosis of Barrett's esophagus: a prospective, multicenter study comparing confocal laser endomicroscopy with conventional histology for the identification of intestinal metaplasia in new users.

ABSTRACT

INTRODUCTION: Endoscopic evaluation with high-definition white light endoscopy and random 4-quadrant biopsy (Seattle Protocol) is the current standard of care for the detection of Barrett's esophagus (BE). Recently, enhanced imaging technologies have become available to provide real-time diagnosis of intestinal metaplasia (IM) and dysplasia, reducing the need for tissue biopsy. Probe-based confocal laser endomicroscopy (pCLE) provides dynamic microscopic mucosal views, rapidly capturing digital images that become optical biopsies. This study examined the role of pCLE in BE screening and surveillance as compared to the Seattle Protocol. METHODS: Patients undergoing BE screening or surveillance endoscopy were enrolled at eight US centers. Optical biopsy using pCLE was interpreted in real time. Endoscopists performing pCLE were new users with a median experience of 8.5 months and no formal training in surgical pathology. Seattle Protocol biopsies were then taken. Recorded pCLE images were reviewed by a blinded expert in optical biopsy interpretation. RESULTS: Early pCLE users identified significantly more patients with IM than the Seattle Protocol overall (99/172 vs. 46/172, p < 0.0001). Early users of pCLE also identified significantly more patients with IM than the Seattle Protocol in the patients with visible columnar lined esophagus (75 vs. 31, p < 0.0001), but not in the 76 patients without columnar lined esophagus (24 vs. 15, p = 0.067). There was no statistically significant difference between early pCLE users and expert review. CONCLUSION: Optical biopsy using pCLE technology allows for the real-time evaluation of entire segments of columnar lined esophagus. Consequently, pCLE is considerably more sensitive in the detection of BE than the Seattle Protocol, which leaves a majority of epithelium unexamined. This effect is seen even in new users and increases with experience. Overall, pCLE provides a promising advance in Barrett's detection which will likely result in superior identification of individuals at risk for esophageal adenocarcinoma.