In patients with non-small cell lung cancer, not only PD-L1 expression in the biopsy specimen increased from 1% to 48% after chemoradiation, but there was also a significant increase in PD-L1 expression in circulating tumor cells (CTC) during treatment, suggesting a natural response of tumor cells to escape the immune response induced by radiotherapy (75, 76). This evidence concerns the gene CD274 and non-small cell lung carcinoma.