EGFR and non-small cell lung carcinoma: Studies have found that EGFR mutations occur in over 20% of NSCLC patients, which suggests sensitivity to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) such as erlotinib and gefitinib [45, 46], but about 10% of patients will develop resistance within 10–16 months [47].