Abstract
OBJECTIVE: To investigate the clinical value of serum tumor markers - carcinoembryonic antigen (CEA), endothelial cell-specific molecule-1 (ESM-1), neuron-specific enolase (NSE), and cytokeratin 19 fragment (CYFRA21-1) - in the diagnosis of lung cancer, and to evaluate the role of preoperative imaging in lung cancer diagnosis. METHODS: A total of 56 lung cancer patients, diagnosed at The Fourth Hospital of Daqing City between January 2022 and December 2023, were included in the lung cancer group. Additionally, 69 patients with benign pulmonary tumors diagnosed during the same period were included in the benign tumor group. Preoperative peripheral serum levels of CEA, CYFRA21-1, NSE, and ESM-1 were compared between the two groups. The expression profiles of these biomarkers were further analyzed, focusing on their correlation with TNM staging, lymph node metastasis, and tumor differentiation. Receiver operating characteristic (ROC) curves were plotted to assess the diagnostic performance of these biomarkers. Imaging characteristics were also compared between the two groups to identify features indicative of lung cancer. RESULTS: Serum levels of CYFRA21-1, CEA, ESM-1, and NSE were significantly higher in the lung cancer group compared to the benign tumor group (all P < 0.05). Pathological analysis revealed that these markers were notably associated with low to medium tumor differentiation, lymph node metastasis, and advanced stage (III-IV) (all P < 0.05). Additionally, small cell lung cancer patients exhibited higher positive rates of CYFRA21-1 and elevated levels of CEA, ESM-1, and NSE compared to non-small cell lung cancer patients. ROC curve analysis demonstrated AUC values of 0.878, 0.778, 0.773, and 0.654 for CYFRA21-1, CEA, ESM-1, and NSE, respectively. Imaging features, including spiculated margins, lobulation, pleural retraction, vascular convergence, vacuolar signs, and larger nodule size, were more prevalent in lung cancer patients and were identified as independent risk factors for lung cancer. CONCLUSION: Peripheral serum biomarkers, including CYFRA21-1, CEA, ESM-1, and NSE, demonstrate significant diagnostic potential for lung cancer. Furthermore, imaging characteristics provide valuable insights for distinguishing lung cancer, underscoring the clinical applicability of both diagnostic approaches.