Due to limited access to biopsies, particularly from SCLC patients and metastatic NSCLC patients, we aimed to investigate the potential of STING pathway activation through the evaluation of mRNA expression of cGAS-STING and downstream chemokines CXCL10/CCL5 in total PBMCs from LC patients and their correlation to the clinical response to anti-PD-L1 blockade. This evidence concerns the gene CGAS and small cell lung carcinoma.