In 2020, Peng et al. [97] investigated the potential use of exosomal miRNAs from the plasma of patients with advanced epidermal growth factor receptor/anaplastic lymphoma kinase (EGFR/ALK)-negative NSCLC that received PD-1/PD-L1 inhibitors as biomarkers for the identification of patients with a positive response to immunotherapy. This evidence concerns the gene PDCD1 and non-small cell lung carcinoma.