A change in the normal or physiologic “stress” on an organ leads to an adaptive change in the type of cells that make up its lining. This change in cell type is called metaplasia, and it commonly involves a change of one type of surface epithelium to another that is better able to handle the new stress.
Barrett’s esophagus is a condition that affects the lining of the lower esophagus, the part of the gastrointestinal tract that connects the throat to the stomach. It is a well-known complication of gastroesophageal reflux disease (GERD), which is a chronic condition that occurs when stomach acid frequently flows back into the esophagus. When the lining in the esophagus is exposed for a prolonged duration to the reflux contents, it can lead to erosion and inflammation of the esophageal mucosa. This damage leads to metaplasia or the replacement of the esophageal lining or stratified squamous epithelium (better suited to handle friction of the food bolus) with one that resembles the stomach’s and is better able to handle the stress of acid (mucin-producing columnar epithelium). This transition is considered to be a premalignant change, which means that under persistent stress it can progress to dysplasia and eventually result in esophageal cancer (adenocarcinoma of the esophagus). In theory, with the removal of the driving stressor (treatment of GERD), metaplasia (Barrett’s esophagus) is reversible.
Barrett’s esophagus is named after Australian thoracic surgeon Norman Barrett. The definition of this condition has evolved over the last century. In 1906, it was described by a pathologist as peptic ulcer of the esophagus. Over the next four decades, the debate revolved on the anatomic origin of the mucosal anomaly. In 1950, Barrett supported the ideology that the stomach was tethered within the chest due to a congenitally short esophagus. However, in 1953, it was argued by Allison and Johnstone to be esophageal tissue and was agreed by Barrett in 1957. The histologic description for the next two decades vary and by 1976, a report on the histologic spectrum of the condition was published where biopsies were performed using manometric guidance.