EGFR and non-small cell lung carcinoma: Although the majority of patients with EGFR mutated (EGFRmut) NSCLC do have a response to EGFR TKIs, 20–30% of patients do not respond to EGFR TKIs or respond for a short time, usually less than 3 months, due to primary resistance to EGFR TKIs [13,15].