Ancillary Studies in the Diagnosis and Classification of Barrett Esophagus: What's on the Menu?

Barrett's esophagus confers an increased risk for esophageal adenocarcinoma. Accurate detection and risk stratification of patients with Barrett's esophagus presents certain challenges. Current paradigms rely on endoscopic examination and histologic diagnosis in forceps biopsies, but this approach is limited by sampling error and interobserver variability. A variety of ancillary studies have been developed to attempt to address these limitations. These techniques employ alternative sampling strategies and/or detection of molecular and protein-level alterations associated with neoplastic progression. This article provides an overview of ancillary studies, including p53 immunohistochemistry, TissueCypher (Tissue Systems Pathology Test-9 [TSP-9]), WATS-3D, and epigenetic assays, among others.