Brahmer [15] did not suggest PD-L1 expression as an effective biomarker of selecting patients for PD-1/PD-L antibody therapy, especially when those with tumors lacking PD-L1 expression (PD-L1 < 1%) has also been observed to derive benefit from PD-1/PD-L1 antibodies in advanced NSCLC. This evidence concerns the gene PDCD1 and non-small cell lung carcinoma.