What are Gastrointestinal Stromal Tumors (GIST)?

Gastrointestinal stromal tumors (GISTs) are a type of soft tissue tumor. GISTs are very rare tumors that start in special cells in the wall of the GI tract, called the interstitial cells of cajal. These cells, often called the "pacemaker cells," regulate body processes like digestion and send signals to the muscles within the gastrointestinal tract to expand and contract, moving food and liquid through the digestive system.

GISTs can occur anywhere within the digestive tract, but are found most frequently in the stomach or small intestine.