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What is Barrett's esophagus is diagnosed by and explain in detail?
Ans. (b) Intestinal metaplasiaRef: Sabiston 19th edy page 1033* Barretts esophagus is characterized by metaplasia of esophageal squamous epithelium into columnar in distal esophagus.* For diagnosis of Barretts esophagus it requires both endoscopically visible segment of columnar lining of distal esophagus and intestinal metaplasia showing goblet cells on biopsy.* Barretts esophagus is the single most important risk factor for adenocarcinoma of esophagus.* Adenocarcinoma develops at the squamo-columnar junction or within 2 cm from the junction.