PDCD1 and chronic obstructive pulmonary disease: (a) p-value, probability-value; based on separate Chi-square tests; (b) aspirin/aggregated immunotherapy, combined aspirin use and immunotherapy of any type;  (c) PD-1, programmed cell death-1; (d) PD-L1, programmed death-ligand 1; (e) COPD, chronic obstructive pulmonary disease; (f) ECOG, Eastern Cooperative Oncology Group; (g) NSCLC, non-small-cell lung cancer