EGFR and non-small cell lung carcinoma: In one prospective study, non-small cell lung cancer (NSCLC) patients with EGFR (epidermal growth factor receptor) exon 20 p.T790M positive mutations in plasma cfDNA had similar results as those treated with tissue tests using the EGFR inhibitor osimertinib (total response rates were 63% and 62%, respectively) [65].