In the United States, the incidence of esophageal adenocarcinoma has risen faster than any other malignancy in recent years, and now represents the most common histologic type of esophageal cancer observed in major institutions. The precise etiology of this malignancy, and the epidermiologic variables responsible for its dramatically rising incidence, remains obscure. Elucidation of the molecular biology of malignant transformation in Barrett's esophagus may improve the management of patients with advanced esophageal adenocarcinomas. Furthermore, appreciation of the molecular events associated with esophageal adenocarcinomas. Furthermore, appreciation of the molecular events associated with esophageal adenocarcinogenesis may facilitate early detection of occult carcinomas, and enable therapeutic interventions designed to prevent these otherwise highly lethal neoplasms.