RecruitingPhase 2Drug trialOsimertinib Therapy After Resection in High-risk Stage I EGFRm NSCLC (OSTAR)This is a prospective, open, single-center, single-arm phase II clinical study with common EGFR-sensitive mutations (Ex19del and L858R) identified in the central laboratory.To evaluate the efficacy and safety of adjuvant Osimertinib therapy in completely resected stage I non-squamous non-small cell lung cancer (NSCLC) with high-risk factors (solid and/or micropapillary component ≥10%, and/or airway spread).