Significant heterogeneity was identified (I2 = 77.5%, P < .001), and pooled results with a random effect model indicated no association between PD-L1 expression and the OS in EGFR-mutant NSCLC (HR [95% CI] = 1.43 [0.98–2.08], P = .062) (Fig. 5). The gene discussed is EGFR; the disease is non-small cell lung carcinoma.