Epidermal growth factor receptor (EGFR) is a cell-surface receptor with intrinsic intracellular protein-tyrosine kinase (TK) activity. Ligand binding induces EGFR dimerization and phosphorylation, leading to the activation of EGFR signaling pathway. In several malignancies such as non-small cell lung cancer (NSCLC), EGFR signaling is deregulated due to mutations in EGFR, which results in uncontrolled proliferation and migration of tumor cells. EGFR mutations can lead to "oncogene-addicted" cancers, where the tumor cells depend on the mutated EGFR for cell survival and malignant phenotype. The EGFR L792H, L858R mutations involve point mutations that changes a L (Leu) into an H (His) at point 792, and a L into an R (Arg) at point 858.