Retrospective analysis was performed on the clinical and sequencing data obtained from eleven patients with lung adenocarcinoma who acquired MET amplification....Acquired MET amplification was detected in four and seven patients who progressed from first-line gefitinib and second-line osimertinib, respectively. Six and five patients received a combination of either first-generation (gefitinib, erlotinib, or icotinib) or third-generation (osimertinib) EGFR-TKI and crizotinib, respectively. Nine patients achieved partial response, resulting in an overall response rate of 81.8 %. The median progression-free survival of the cohort was 5.8 months.