PD‐L1 Expression and Histopathological Features in EGFR‐Mutated Non‐Small Cell Lung Cancer: Implications for Immune Checkpoint Inhibitors After EGFR‐Tyrosine Kinase Inhibitors Resistance

Epidermal growth factor receptor‐mutated (EGFRm) non‐small cell lung cancer (NSCLC) responds well to EGFR tyrosine kinase inhibitors (EGFR‐TKIs), yet optimal therapy after resistance remains uncertain. Although immune checkpoint inhibitors (ICIs) show limited overall efficacy, heterogeneity in response by programmed cell death ligand 1 (PD‐L1) expression exists.