The esophagus is a long muscular tube that connects the pharynx (throat) to the stomach. It travels behind the trachea in the neck and thoracic regions of the body, passes through the diaphragm and gets into the uppermost region of the stomach. The esophagus is about 9-10 inches in length. The wall of the esophagus consists of four distinct tissue layers: mucosa, submucosa, muscularis, and adventitia. As the important component of the digestive system, the esophagus function as a conduit for delivering food and liquid to stomach aided by peristaltic contractions. And the upper esophageal sphincter (UES) and the lower esophageal sphincter (LES) of the esophagus will regulate this process accurately. The diseases may appear when some part of the esophagus tissue has problems. Some conditions like esophagitis, esophageal ulcer, or esophageal cancer are common clinical disorders. A variety of target molecules expressed on esophagus tissue has been used for detection of esophagus disease.
