Summary This is a research study that will look at genetic information in tissue to help find out more information about Barrett's esophagus and the development of dysplasia (pre-cancer) and esophageal cancer arising from within the Barett's esophagus. This is a disease that is increasing in frequency. Barrett's esophagus is a condition where the superficial lining of the esophagus changes and is associated with higher risk of developing cancer of the esophagus. Presently patients with Barrett's esophagus require surveillance endoscopies and biopsies on a regular basis. Only some patients however progress to cancer and it is unclear what differentiates those who progress to cancer from those that do not. This study is aimed at finding markers in the tissues to help identify patients more or less likely to progress. Esophageal adenocarinoma (EAC), a lethal cancer with very high mortality rates, is increasing alarmingly in incidence and results from dysplastic progression of Barrett's esophagus (BE). Patients with BE have a 30-125 increased risk of developing EAC compared to the general population.