In our previous study, we noticed a correlation between a greater proportion of CD45RO+CD62L (central memory phenotype) to CD45RO+CD62L (effecter memory phenotype) on CD4+T cells and a more favorable clinical outcome of PD-1 blockade in patients with lung cancer, although the results were not statistically significant, possibly owing to the limited sample size. This evidence concerns the gene PDCD1 and lung cancer.