GRP and chronic lung disease: Univariable logistic regression analysis showed that age, gender, body mass index, smoking history, chronic lung disease, abnormal pulmonary function, size, CTR, and CT values of PNs, BEAS or cavity sign, lobulation, spiculation, pleural traction, vascular convergence, and blood tumor marker (CEA, CYFRA21-1, SCC, Pro-GRP, and NSE) levels were potential risk factors (P< 0.2).