Barrett's Esophagus and esophageal adenocarcinoma.

The incidence of esophageal adenocarcinoma (EAC) has risen dramatically over the past three decades in western countries. The importance of Barrett's esophagus (BE) derives from its potential to transform to adenocarcinoma. BE is characterized by endoscopically recognized displacement of the squamocolumnar junction proximal to the gastroesophageal junction, with replacement of squamous mucosa with columnar lined mucosa. Adenocarcinomas of the esophagus appear to arise from Barrett's mucosa through progressive degrees of dysplasia, but the pathogenesis and natural history of this process are still unclear. Much of our knowledge regarding BE and the risk of EAC is based on observational and cross-sectional analyses, and recommendations regarding management have traditionally represented "expert opinion." The past few years have seen an explosion in new information and the initiation of longitudinal studies to define the risk of adenocarcinoma in BE, the identification of predictive and prognostic markers of cancer risk, sensitive and cost-effective methods of surveillance, and methods of management of dysplasia and early neoplasia including disease prevention.