What is gastrointestinal stromal tumor (GIST)?
GIST is a rare cancer of the GI track. It belongs to the general class of cancers called sarcomas. Sarcomas are a group of rare cancers that occur in connective tissues, bones, and muscle tissues. Sarcomas are derived from “mesenchymal cells”, which are a general class of cells that includes fibroblasts, muscle cells, blood vessel lining cells (=endothelial cells) About 40-70% of GISTs arise from the stomach, 20-40% arise from the small intestine, and 5-15% from the colon and rectum. GISTs can also be found in the esophagus (<5%), omentum (<5%), mesentery, or retroperitoneum. GIST should not be confused with more common cancers (carcinomas) of the GI tract, such as stomach or colon carcinomas; carcinomas may occur in the same parts of the body, but their origins and treatments are complet ely different.