Because the pretreatment frequency of CX3CR1+ CD8+ T cells was variable between patients, to assess the effect of anti-PD-1 therapy on NSCLC patient’s CD8+ T cells, we calculated the percent change from baseline in the frequency of the CX3CR1+ subset in PB CD8+ T cells at all post-treatment time points available (3–12 wk post-treatment initiation). The gene discussed is PDCD1; the disease is non-small cell lung carcinoma.