CD274 and cancer: In this proof of concept study, we investigated the prognostic value of different liquid biopsy biomarkers (CTCs, PD-L1+ CTCs, sEVs, PD-L1+ sEVs, and ctDNA) alone, and in combination, in a cohort of patients with NSCLC, regardless of cancer treatment, subtype, and stage, to determine whether their combination gives more precise prognostic information.