Adjuvant therapy with imatinib in gastrointestinal stromal tumors (GISTs)—review and perspectives

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumor of the gastrointestinal (GI) tract. Most of them (>75%) are driven by an oncogenic initiating event involving activating mutations of the genes encoding for tyrosine kinase, KIT or platelet derived growth factor receptor alpha (PDGFRA). Efficacy of the tyrosine kinase Inhibitor imatinib is now well established for advanced disease. For localized GISTs, 3 years treatment is the recommended adjuvant therapy for high risk patients. Whether a longer duration and selection of patients for this adjuvant therapy in localized GISTs remains is not yet established (PERSIST-5 study). Similarly, it will be important to further refine the definition of the population of GIST patients at high risk of relapse including molecular criteria (Annals of Oncology, ESMO guidelines 2018). This review aims to describe current knowledges on the issue of adjuvant therapy of primary GISTs in view of available results.