Epidermal growth factor receptor (EGFR) is one of the mutated proto-oncogenes in lung adenocarcinoma, where a sensitizing EGFR mutation can result in constitutive activation of tyrosine kinase (TK) and phosphorylation of downstream pathways leading to uncontrolled proliferation, invasion and metastasis. This evidence concerns the gene EGFR and lung adenocarcinoma.