EGFR and chronic obstructive pulmonary disease: Among patients with LC, univariate regression analysis revealed that age ≥ 65 years, male, ex- or current smokers, pack-years ≥ 20, high level of fibrinogen, CPI ≥ 40, tumor EGFR wild-type, advanced lung cancer, and coexistence of COPD, IPF, or CPFE were related to poor survival.