EGFR and adenocarcinoma: The epidermal growth factor receptor (EGFR) is a well characterized mutated oncogene in NSCLC: mutations (exon 19 deletions, exon 18 variants and L858R substitution in exon 21) leading to constitutive kinase activation are found in ∼10–20% of cases in western countries and are associated predominantly with adenocarcinoma histology [2–4].