These findings provide evidence that baseline PD-L1 expression may serve as a prognostic biomarker for patients with EGFR-mutated NSCLC receiving first-line osimertinib and implicate the CD56bright NK cell/IFN-γ/STAT3 axis in the regulation of PD-L1 expression. The gene discussed is IFNG; the disease is non-small cell lung carcinoma.