Area Editoriale
The incidence of esophageal adenocarcinoma has risen steadily over the past 10 years. Patients with Barrett's esophagus are at increased risk for the development of adenocarcinoma.Barrett's esophagus was defined in the past by the macroscopic appearance and length of columnar mucosa in the esophagus. In 1983, Skinner et al. restricted the term Barrett's esophagus to identify only those patients who had columnar epithelium 3 cm or greater in length in the distal esophagus. This criterion was established to prevent overdiagnosis of Barrett's esophagus. Then, in 1994, Spechler et al.published an influential article that stated that goblet cells were present at the gastroesophageal junction in 18% of patients with findings that did not fit the 3 cm of columnar-type epithelium rule. Because goblet cells are a marker of specialized intestinal epithelium, this finding was labeled short-segment Barrett's esophagus. The diagnosis of Barrett's esophagus is established when intestinal metaplasia is found in biopsy specimens obtained from salmon-colored mucosa in the distal esophagus proximal to the junction of the esophagus and stomach. It is this intestinal metaplasia that is associated with the increased risk of adenocarcinoma. The salmon-colored mucosa in the distal esophagus is columnar and consists of a mosaic of fundic mucosa, cardia mucosa, and intestinal metaplasia. Thus, the distribution of intestinal metaplasia within the salmon-colored, columnar mucosa of the esophagus is patchy. The yield of biopsy specimens of columnar-type mucosa in the distal esophagus for the detection of intestinal metaplasia varies from 25% to 50% in short-segment Barrett's esophagus and up to 80% in long-segment Barrett's esophagus.The development of high-resolution and magnifying endoscopy during the past decade has significantly improved the ability to image the GI mucosal surface and target biopsy specimens. Many studies have demonstrated the diagnostic capabilities and limitations of magnifying endoscopy. For the endoscopist unfamiliar with magnifying endoscopy, the images of the mucosal surface may be difficult to interpret. However, magnifying endoscopy was used to evaluate and differentiate benign from malignant polyps in the colon before its use for examination of the upper-GI tract.
Conventional endoscopes image only the mucosal surface. Ideally, a method that improves visualization of the mucosa would aid in the detection of Barrett's esophagus and improve the accuracy of surveillance. Several new and established endoscopic methods are under evaluation.