Although epidermal growth factor receptor (EGFR) mutations and anaplastic lymphoma kinase (ALK) rearrangement tend to have high PD-L1 expression due to the activation of signaling pathways (39, 40), the low mutation or neoantigen load (41), along with the following mechanisms, impairs the immunotherapy sensitivity in this group of patients with lung cancer. Here, EGFR is linked to lung cancer.