MET exon 14 skipping mutation (MET∆ex14) is present about 3% of non-small cell 
lung cancers (NSCLCs). NSCLC patients with MET∆ex14 are characterized by an 
average age of over 70 years at diagnosis, a smoking history and a higher 
frequency in pleomorphic carcinoma and adenosquamous cell carcinoma than in 
adenocarcinoma. It has also been reported that NSCLCs with MET∆ex14 often have 
codriver alterations such as EGFR amplification (6-28%), FGFR1 alterations 
(5-17%), KRAS alterations (~8%), BRAF alterations (~21%), or PIK3CA 
mutation/amplification (~14%). In 2020, the approval of two MET-tyrosine kinase 
inhibitors (TKIs), capmatinib and tepotinib, for NSCLCs carrying MET∆ex14 dawned 
a new era for MET-targeted therapy. These drugs yielded progression-free 
survival of 5.4-12.4 months in clinical trials; however, it has also been 
reported that one-third to half of patients show inherent resistance to 
MET-TKIs. In addition, the emergence of acquired resistance to MET-TKIs is 
inevitable. In this review, we summarize the clinical and molecular 
characteristics of NSCLCs with MET∆ex14, the efficacy and safety of capmatinib 
and tepotinib, the inherent and acquired resistance mechanisms to MET-TKIs, and 
new treatment strategies for NSCLCs with MET∆ex14 in the near future.