This is a multicenter, retrospective observational real-world study, which evaluates the efficacy of Osimertinib, between 2017 and 2022, in patients with advanced or metastatic EGFR 20exon insertion mutation (20ins) Non-Small Cell Lung Cancer. This study serves as the external control for a single arm phase II trial on JMT101 combined with Osimertinib in patients with Non-Small Cell Lung Cancer. The primary outcome measure is objective response rate (ORR).
