Tyrosine kinase inhibitors (TKIs; e.g., imatinib, sunitinib, regorafenib, ripretinib) were hypothesized to block the constitutive activation of KIT- and PDGFRA-mediated pathways, and have indeed demonstrated anti-tumor activity in clinical trials of patients with advanced GIST [2–8]. This evidence concerns the gene KIT and neoplasm.