Circulating tumor-associated biomarkers and pulmonary function in lung cancer patients with comorbid COPD: A retrospective prognostic analysis.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is closely associated with lung cancer development and progression through persistent systemic inflammation and immune-biochemical alterations. Circulating tumor-associated biochemical biomarkers may reflect disease severity and provide valuable prognostic information. This study aimed to explore the potential association between circulating tumor markers and prognosis in lung cancer patients with comorbid COPD, acknowledging the exploratory nature of this retrospective analysis. METHODS: Clinicopathological characteristics and circulating biochemical biomarkers, including carcinoembryonic antigen (CEA), carbohydrate antigen 125 (CA125), carbohydrate antigen 153 (CA153), carbohydrate antigen 199 (CA199), cytokeratin-19 fragment (CYFRA21-1), and vascular endothelial growth factor (VEGF), were analyzed. Multivariate logistic regression was performed to identify independent prognostic biochemical predictors. Receiver operating characteristic (ROC) curve analysis was used to evaluate prognostic performance.