Giant Abdominal Gastrointestinal Stromal Tumors with Preoperative Treatment

Gastrointestinal stromal tumors are the most common gastrointestinal mesenchymal tumor and are most commonly found in the stomach (50–60%) and small intestine (20–30%) [1]. It is currently believed that the possible origin of GIST is the interstitial cells of Cajal, which control gastrointestinal peristalsis [2]. Extra-gastrointestinal stromal tumor (EGIST) refers to GIST that occur outside the gastrointestinal tract, and are common in the omentum, mesentery, and retroperitoneum [3]. Both EGIST and GIST have similar cell morphology, immunohistochemical expression, and gene mutation types, but because they have no obvious symptoms in the early stage, EGIST tumors are often large when they are discovered. This report describes a typical huge EGIST case.