EGFR and glioblastoma: Remarkable heterogeneity in amplification of the RTK genes EGFR, MET, and PDGFRA in GBM has been reported in genomic and in situ studies (Little et al., 2012; Snuderl et al., 2011) and there is accumulating evidence that mosaicism of molecular patterns has profound implications for the design of effective chemo and targeted therapeutical regimens (Sottoriva et al., 2013).