Pathologic aspects of tumors of gastrointestinal tract in the era of personalized medicine

The gastrointestinal (GI) tract is an anatomic term used to denote the tubular digestive system and its accessory organs. It is often divided into the upper GI tract, lower GI tract, and accessory organs for purposes of discussing its diseases. The upper GI tract consists of the esophagus, stomach, and duodenum, whereas the lower GI tract comprises the remainder of the small intestine, the colon, and the anus. The accessory organs include the liver, gallbladder, pancreas, and the hepatobiliary and pancreatic ducts.