gastrointestinal disorders
Gastrointestinal Stromal Tumors (GISTs)
Introduction
Gastrointestinal stromal tumors are tumors of the gastrointestinal tract derived from mesenchymal precursor cells in the gut wall (interstitial cells of Cajal). Diagnosis is usually by endoscopy. Treatment is surgical removal. Gastrointestinal stromal tumors (GISTs) are categorized as a type of soft-tissue sarcoma and are the most common type of sarcoma arising within the GI tract. Overall, they are very rare with approximately 4000 to 6000 new cases annually in the United States ( General references ). gene ( General references ). Some are caused by previous radiation therapy to the abdomen for other tumors. The remainder are caused by a variety of less common mutations and are generally referred to as wild-type GISTs. In one study, 51% of GISTs occurred in the stomach, 36% in the small bowel, and a small number in the esophagus, colon, and rectum ( General references ). Average age at presentation is 50 to 60. GISTs may arise in people with a genetic syndrome. The two most common are Neurofibromatosis None Familial SDH deficiency (Carney-Stratakis syndrome) GISTs are often slow growing, but they exhibit a wide array of malignant potential. The malignant potential of a particular GIST is related to where in the GI tract it originates, the size of the primary tumor, and the mitotic rate seen on biopsy (or surgical pathology). Of these, small tumors in the stomach with a low mitotic rate have the most favorable outcomes. Those measuring < 2 cm have very low malignant potential (2 to 5%) and are often managed by observation. Symptoms of GISTs vary with location but include bleeding, Dyspepsia , and obstruction. They are also commonly identified incidentally on imaging that is done for another reason. 