The Serum Tumor Markers in Combination for Clinical Diagnosis of Lung Cancer

Background To explore the clinical value of combined detection of serum tumor markers in lung cancer, including carcinoembryonic antigen (CEA), carbohydrate antigen 15-3 (CA15-3), cytokeratin 19 fragment (CYFRA 21-1), neuron specific enolase (NSE), and squamous carcinoma antigen (SCCA). Methods The expression levels were compared among groups, and the combined effects of these tumor markers in the diagnosis of lung cancer were analyzed. In addition, EGFR gene mutations were detected in some patients with NSCLC. Results There were 776 patients (age 59.78 ± 10.39 years) with lung cancer and 794 controls (age 58.26 ± 15.73 years) included in our study. In this study, tumor markers were detected in lung cancer patients and controls. Individual sensitivity of the tumor markers sorted in descending order were CEA > CYFRA21-1 > CA15-3 > NSE, and the specificities were NSE > CYFRA21-1 > CEA > CA15-3. The combination of CEA + CA15-3 + CYFRA21-1 + NSE ranked the highest in the sensitivity index (75.00%) and specificity index (98.61%) in lung cancer. In adenocarcinoma, the area under the ROC curve (AUROC) of CEA (0.665) and CYFRA21-1 (0.631) were higher than those of CA15-3 (0.559) and NSE (0.507). In squamous carcinoma, the AUC of CYFRA21-1 (0.722) and SCC (0.628) were higher than those of CEA (0.579), CA15-3 (0.524), and NSE (0.552). In small cell carcinoma, the AUC of NSE (0.654) was higher than those of CEA (0.616), CYFRA21-1 (0.555), and CA15-3 (0.482). Conclusions These serum tumor markers are valuable indicators in the clinical use. The combination of tumor markers can be used as a method to improve the effectiveness of clinical diagnosis for lung cancer.