Four genes increased concordantly in EGFR-amplified tumours in both primary and recurrent samples: EEA1 (co-localising early endosomal antigen 1 with the EGFR–EGF complex as it enters intracellularly [18]), IVD (isovaleryl-coA dehydrogenase), SEC61G (co-expressed with EGFR on chr 7p11 [19]), and EGFR itself. Here, EGF is linked to neoplasm.