In non-small cell lung cancer (NSCLC), T790M is a very common point mutation was detected in 60% of patients with EGFR TKI resistance.86,87 C797S mutations were described as responsible for acquired resistance to third generation EGFR-TKI and was found in 40% of patients with mutant NSCLC with T790M mutation. Here, EGFR is linked to non-small cell lung carcinoma.