PDGFRB and hepatocellular carcinoma: Sorafenib is an inhibitor of several signal pathways including RAF/ERK/MERK, c-MET, vascular endothelial growth factor receptor (VEGFR) and platelet-derived growth factor receptor (PDGFR), with a great potential in biologically heterogeneous tumors [4], but its efficacy in HCC is unpredictable, heterogeneous and not easy to evaluate.