The pharmacological activity of sunitinib as a multi-kinase inhibitor targeting several tyrosine kinases including those of vascular endothelial growth factor receptor (VEGFR), PDGFR and KIT [27], and clinical activity in GIST patients with wild-type KIT [28] is consistent with the activity of this agent in our case series. This evidence concerns the gene PDGFRB and gastrointestinal stromal tumor.