EGFR and lung adenocarcinoma: Over the last two decades, many oncogenic drivers, such as epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), v-raf murine sarcoma viral oncogene homolog B (BRAF), ROS proto-oncogene 1 (ROS1), Kirstin rat sarcoma virus (KRAS), human epidermal receptor 2 (HER2), c-MET proto-oncogene (MET), have been identified in approximately 60% of lung adenocarcinoma patients in Western populations and 80% among Asian population 4.