PDCD1 and lung cancer: Among patients with AD, higher expression of the PD1 and PDL1 genes was a significantly protective factor in terms of relapse and outcomes in early-stage lung cancer patients (P-value for HR<0.05), but the significance of high PDL1 expression as a protective factor was borderline (HR=0.63; 95% CI=0.39 ~ 1.00; P=0.0514).