EGFR and lung cancer: Based on histopathology, non-small cell lung cancer (NSCLC) is a major type of lung cancer; it accounts for almost 80% of lung cancers and exhibits intrinsic resistance to anticancer drugs, including platinum-based antineoplastic drugs [1, 2] and epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) [3, 4].