Gastrointestinal stromal tumors of the stomach and duodenum

Purpose of review Gastrointestinal stromal tumors (GISTs) are rare, malignant neoplasms of the gastrointestinal tract which are in most cases driven by oncogenic mutation of KIT or PDGFRA. GISTs may arise anywhere along the gastrointestinal tract but the stomach is the most common primary location, whereas duodenal GISTs are rare. New data regarding the adjuvant treatment of these tumors were recently reported and are likely to impact patient management. Recent findings In this article, we review the diagnostic, prognostic and therapeutic specificities of gastric and duodenal GISTs. Also, specificities in the molecular biology of gastric and duodenal GISTs are discussed. Summary Gastric GISTs are relatively frequent and recent data indicate that imatinib-resistant PDGFRA-D842V mutation may be found in up to 10% of cases of localized gastric GISTs and this impacts the prescription of adjuvant imatinib. Duodenal GISTs, on the contrary, are rare and have rather poor prognosis. Furthermore these tumors frequently harbor KIT exon 9 mutations for which the adequate dose of adjuvant imatinib is debated.