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 gas- trointestinal tract. Approximately 60-70% are located in the stom- ach. 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 ex- amination for other pathologies or at autopsy. The most common symptoms of gastric GIST are abdominal pain and bleeding. Diag- nostic 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. (Acta gastro- enterol. belg., 2013, 76, 403-406).