Such debate has been sustained by a number of studies showing that the expression of PD-L1 in some NSCLC patients was low or even negative, but the response to anti-PD-1/PD-L1 treatment was better [36,37] on the other hand, some patients had higher expression of PD-L1, and the therapeutic effect of anti-PD-1/PD-L1 therapy was poor. The gene discussed is PDCD1; the disease is non-small cell lung carcinoma.