Barrett's esophagus occurs when the inflamed and potentially ulcerated squamous mucosa of the esophagus undergoes metaplasia to columnar mucosa. This columnar mucosa contains goblet cells and is therefore known as intestinal metaplasia. BE is diagnosed when an endoscopist sees columnar mucosa in the distal esophagus and the pathologist identifies intestinal metaplasia on biopsy from the abnormal area. This disease is important because it is the predisposing factor for the development of adenocarcinoma of the esophagus. It occurs in approximately 10% of individuals with symptomatic gastroesophageal reflux disease (GERD), and is associated with a 30-fold increased risk of developing cancer compared with the normal population. The mean annual incidence of cancer in patients with longstanding BE is reported to be approximately 0.5%.
Fortunately, development of adenocarcinoma in BE occurs through sequential steps of low grade dysplasia through high grade dysplasia and then to adenocarcinoma. Dysplasia can only be identified by pathological interpretation of biopsies, and therefore, patients with BE undergo periodic endoscopies (surveillance) at which time biopsies are taken. If low grade dysplasia is found, patients are treated more aggressively with medication and then re-biopsied in the short term. If high grade dysplasia is present, patients will be considered for esophagectomy. The medical treatment of BE is with drugs that lower gastric acid production, in particular, parietal cell proton pump inhibitors such as omeprazole.