Sunitinib (sunitinib malate; Sutent; Pfizer Inc, New York, NY) is an orally multitargeted tyrosine kinase inhibitor known to inhibit vascular endothelial growth factor receptors (VEGFRs), platelet-derived growth factor receptors (PDGFR), c-KIT, Fms-like tyrosine kinase 3 receptor (FLT3) and receptor encoded by the ret proto-oncogene.[5–7] Currently, sunitinib is given as first-line treatment to advanced renal cell carcinoma (RCC) and imatinib-resistant gastrointestinal stromal tumor (GIST). This evidence concerns the gene PDGFRB and gastrointestinal stromal tumor.