Adenocarcinoma of the esophagus

The esophagus is a strong muscular tube that moves food from the oropharynx to the stomach. The lumen of the esophagus is lined by a thick protective stratified squamous epithelium. Underlying the epithelium is the lamina propria (containing scattered lymphoid aggregations) and the muscularis mucosa. The highly vascular submucosa lies below the muscularis mucosa and contains small mucous glands that aid in lubrication. These glands are located in the distal third of the esophagus. The muscularis propria is a thick inner circular and outer longitudinal layer of smooth muscle. In the proximal third of the esophagus, skeletal muscle can be seen in the muscularis mucosa (as the first part of swallowing is under voluntary control).