Several studies have sequentially evaluated the association of a response to the PD-1 blockade with the number of CTCs or PD-L1 expression on CTCs in NSCLC patients [21,28,29]; however, almost every study evaluated approximately 10–20 cases, and there were few cases in which the blood samples were both frequently and longitudinally evaluated. Here, CD274 is linked to non-small cell lung carcinoma.