This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Esophageal disorders, Subject name: Pathology
Barrett's esophagus result in which type of carcinoma: 
Select and explain. 
A. Adenocarcinoma, B. Squamous cell, C. Adenosquamous, D. Basal cell carcinoma
A: Adenocarcinoma
Answer: A: Adenocarcinoma 
Explanation: Barret's esophagus: Intestinal metaplasia of squamous cells of esophagus d/t reflux of gastric acid Stratified squamous epithelium of esophagus is replaced by nonciliated columnar epithelium with goblet cells. Increases risk of esophageal adenocarcinoma Interstitial like columnar cell has goblet cells which secrete mucin - identified with stain called Alcian blue