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What is Barrett's esophagus is characterised by which of the following histologic change? and explain in detail?
Barrett's esophagus is a condition in which squamous epithelium of the esophagus is replaced by metaplastic columnar epithelium containing goblet and columnar cells in some patients with GERD. Barrett's epithelium is a major risk factor for adenocarcinoma of the esophagus due to proximal displacement of the squamocolumnar junction. In patients with more than 10 year history of GERD should undergo a screening EGD for Barrett's esophagus. Endoscopic biopsy is the gold standard for confirmation of Barrett's esophagus, and for dysplasia or cancer arising in Barrett's mucosa. Ref: Harrison's Principles of Internal Medicine, 18e chapter 291.