84

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the digestive tract and most often result from activating mutations in the KIT or PDGFRA genes. Their diagnosis relies on morphology and immunohistochemistry, with characteristic expression of KIT (CD117) and DOG1. Tyrosine kinase inhibitors (TKIs), particularly imatinib, have revolutionized GIST management, significantly improving patient survival. The “wild-type” GISTs, lacking KIT or PDGFRA mutations, comprise distinct subtypes, including SDH-deficient GISTs and those harboring BRAF, NF1, or NTRK alterations.The identification of the molecular profile of GISTs is a critical step for optimal patient management, as both the choice of TKI and its dosing directly depend on the tumor mutational status.