Gastrointestinal Stromal Tumor (GIST): About 3 Cases

Abstract

Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors that typically occur in the gastrointestinal tract. About 70% of GISTs are benign, while approximately 30% are malignant. GISTs represent less than 0.1% to 3% of all gastrointestinal tumors. These tumors are thought to originate from intestinal cells of Cajal (ICCs) or stem cell-like precursors. ICCs, often referred to as the "pacemaker" cells of the GI autonomic nervous system, regulate GI motility and are found around the myenteric plexus and the muscularis propria throughout the GI tract.   GISTs are composed of different types of cells: approximately 70% are spindle cells, 20% are epithelioid cells, and 10% are mixed cells. Around 85% of GISTs contain mutations in one of two receptor tyrosine kinases (RTKs), KIT or PDGFRA, which play a central role in the pathogenesis of these tumors. Additionally, about 95% of GISTs test positive for the CD117 antigen. Clinically, GISTs are most commonly found in the stomach (60%), followed by the small intestine (30%), duodenum (5%), rectum (3%), colon (1%), and oesophagus (0.5%). Occurrences in the omentum and mesentery are rare. GISTs affect men and women equally and most commonly occur between the ages of 50 to 70 years. The annual incidence rate is between 6.5 and 14.5 per million people worldwide. In our study, we report three cases of GISTs located in the duodenum, jejunum, and transverse colon. Diagnosis in these cases was confirmed via CT scan and all cases tested positive for the CD117 antigen.