Endoscopy in premalignant conditions of the esophagus.
D000230:Adenocarcinoma / Q000175:diagnosis; D001471:Barrett Esophagus / Q000175:diagnosis; D002278:Carcinoma in Situ / Q000175:diagnosis; D004938:Esophageal Neoplasms / Q000175:diagnosis*; D004945:Esophagoscopy; D006801:Humans; D011230:Precancerous Conditions / Q000175:diagnosis*; D012306:Risk; D013194:Staining and Labeling