Abstract: Objective： To investigate the diagnostic value of serum tumor marker in solitary pulmonary nodules (SPN). Methods: In the study, 175 cases of SPN postoperatively diagnosed by pathology between Jan. 2011 and Jan. 2013 in Peking University First Hospital were selected, including 125 cases of lung cancer and 50 cases of benign lesions. The levels of serum carcino-embryonic antigen (CEA), squamous cell carcinoma (SCC), neuron-specific enolase (NSE) and cytokerantin-19-fragment (CYFRA21-1) were detected by electrochemical luminescence immunoassay. SPSS 11.5 software package was used for statistical analysis. Results: In the malignant SPN group, CEA, SCC and CYFRA21-1 levels were significantly higher than in the benign group (P<0.05). The positive rates of CEA, SCC, CYFRA21-1 and combined detection of the four serum tumor markers in the malignant SPN group was significantly higher than in the benign group (P<0.05). ROC curves showed that the under-curve area of CEA, NSE, SCC and CYFRA21-1 was 0.633±0.045, 0.494±0.047, 0.664±0.042 and 0.711±0.041, respectively. The combination of CEA, SCC, NSE and CYFRA21-1 showed the highest sensitivity (52.0%) and better specificity (76.0%) for diagnosis of lung cancer. There were no statistical differences in the positive rates of tumor markers between the malignant SPN group and benign group in the smoking patients (P>0.05). Conclusion: CEA, SCC and CYFRA21-1 have higher positive rates in the malignant SPN patients, suggesting a certain value in the early diagnosis of malignant SPN.

Key words: Tumor markers, biological, Solitary pulmonary nodule, Lung neoplasms