PDGFRA and mesenchymal cell neoplasm: GIST is a mesenchymal tumor based on the carcinogenic mutation of the stem cell factor receptor (KIT) or the platelet-derived growth factor receptor alpha (PDGFRA) gene (Hirota et al., 1998; Heinrich et al., 2003), which can be treated with a tyrosine kinase inhibitor (TKI), such as imatinib (Simon et al., 2013; Espinosa et al., 2008).