True about Barret's esophagus -a) Premalignantb) Predispose to sq. cell Cac) Can be diagnosed by seeing under endoscoped) Biopsy is necessary to diagnosee) Stricture may be present in high esophagus

Diagnosis of Barrett's esophagus - The diagnosis of Barrett's esophagus is suspected on endoscopy when there is difficulty in visualizing the squamo-columnar junction at its normal location and by the appearance of pink, more luxuriant columnar mucosa in the lower esophagus instead of gray-pink squamous mucosa. -  the diagnosis is confirmed by biopsy. Strictures in Barrett's esophagus occur at the squamo-columnar junction and move high up as the squamo-columnar junction moves up with progressive injury.