Gastrointestinal stromal tumor of the stomach: progresses in diagnosis and treatment.

Gastrointestinal stromal tumors (GISTs) are rare mesenchymal smooth muscle neoplasms that can arise anywhere within the gastrointestinal tract. Approximately 60-70% are located in the stomach. Once considered variants of smooth muscle tumors, they are now understood as originating from the interstitial cells of Cajal or their stem cell precursors. The majority of GISTs (approximately 95%) express the CD117 antigen (KIT), a proto-oncogene product ; 85-95% of these neoplasms have mutations in the c-KIT gene; only 5-7% has mutations in platelet-derived-growth factor a (PDGFRa). GISTs can be asymptomatic and incidentally found during examination for other pathologies or at autopsy. The most common symptoms of gastric GIST are abdominal pain and bleeding. Diagnostic work up consists of endoscopy with ultrasonography and cross-sectional imaging studies (computed tomography and/or magnetic resonance imaging). Surgery remains the first-line treatment for localized gastric GISTs. Both open and laparoscopic operations have been shown to reduce recurrence rates and improve long-term survival. The use of small-molecule selective tyrosine kinase receptor inhibitors has revolutionized the treatment of advanced GISTs.