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GI Stromal Cancer

Gastrointestinal stromal tumors (GISTs) are uncommon tumors that form in the wall of the gastrointestinal tract from cells known as ICCs, or interstitial cells of Cajal. ICCs are sometimes called gastrointestinal pacemaker cells because they help transmit signals from the autonomic nervous system to the smooth muscles of the gastrointestinal wall, stimulating waves of contraction (peristalsis) that help propel food and waste products through the digestive system. GIST can begin anywhere in the gastrointestinal tract; 60 percent of tumors originate in the stomach, and another 30 percent in the small intestine. Other sites of origin include the esophagus, colon, rectum, and anus. GIST affects about 4,000 to 5,000 people in the United States each year. GIST treatment in adults has been greatly improved by the development of several highly effective targeted therapies. In children, however, the story is very different.