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What is In classic Barret's, the length of columnar epithelium in distal oesophagus is and explain in detail?
Classic Barrett's (>= 3cm columnar epithelium);Sho-segment Barrett's (<3 cm of columnar epithelium);Cardia metaplasia (intestinal metaplasia at the oesophagogastric junction without any macroscopic change at endoscopy).The relative risk of cancer rises with increasing length of abnormal mucosa.