Comparison of Probe-Based Confocal Endomicroscopy to Standard Endoscopy with Biopsies for Patients Who Underwent Endoscopic Mucosal Resection for Barrettʼs Esophagus-related Dysplasia or Intramucosal Adenocarcinoma

Abstract

Purpose: Given the limitations of standard endoscopic surveillance with biopsies after endoscopic mucosal resection (EMR) for Barrett's esophagus (BE) with dysplasia, probe based confocal endomicroscopy (pCLE) may play a role in improving surveillance, targeting biopsies and resections in surveillance. The aim of our study was to examine pCLE exam after EMR to examine for residual dysplasia or intramucosal adenocarcinoma (ICA) and compare to surgical pathology for accuracy. Methods: We selected patients with Barrett's esophagus associated nodules underwent EMR and found to have dysplasia or ICA. These patients then had cap assisted pCLE examination as well as tissue sampling of the prior EMR site on surveillance endoscopy. The same endoscopist with prior pCLE training examined post-EMR (identified by prior documented location) using established pCLE findings (based on the Miami pCLE classification) including flat cells without crypts or villi for normal squamous epithelium; villiform architecture with columnar cells and goblet cells for BE; villiform structures with dark, irregular thickened epithelial borders, dilated irregular vessels for dysplasia and disorganized/loss of villiform structure for adenocarcinoma. The same site was then biopsied (minimum 4 bites) or repeat EMR for pathologic diagnosis. Results: A total of 9 patients with BE with dysplasia (n=6) or ICA (n=3) underwent EMR were examined with pCLE. Two of the patients had pCLE findings consistent with high grade dysplasia (HGD) or adenocarcinoma, characterized by hypervascularity with dark thickened epithelial borders (HGD) as well as irregular atypical cells with disorganized pattern of the villiform structure (ICA). The other seven had pCLE findings showing either squamous epithelium (n=3) or BE without no dysplasia (n=4). The surgical pathologic diagnosis (obtained by repeat EMR n=6; Biopsies n=3 matched pCLE findings in 8/9 patients. In one patient, the pCLE finding was suspicious for HGD but biopsies showed no dysplasia. Conclusion: Accurate surveillance is important post treatment for BE with dysplasia or ICA. pCLE can help target biopsies as well as re-treatment based on findings. In this study, pCLE accurately matched the gold standard in all but one case. A larger prospective study examining pCLE in post EMR sites is warranted.