EGFR and non-small cell lung carcinoma: In the internal cohort of NSCLC cfDNA samples, the major druggable mutation rate was as follows: EGFR, ERBB2, and MET amplification account for 19.7% in EGFR driver mutation positive patients, and account for only 1.92% in EGFR driver mutation negative patients, respectively, which also suggest that EGFR, ERBB2 and MET amplification were enriched in EGFR TKI resistant patients (Odds Ratio: 12.58; Fisher exact test P-value: < 2.2 × 1016).