Among 41 patients who exhibited T790M mutations at enrollment after receiving EGFR-targeted therapy, additional putative resistance mutations were detected in the pretreatment plasma ctDNA of 19 patients (46%), including MET copy-number gains, the target gene alteration for the MET inhibitor crizotinib, which we also detected in 2 patients using both CAPP-Seq of ctDNA and FISH analysis of tumor samples (COL1 and CER3). This evidence concerns the gene MET and neoplasm.