Diagnostic utility of LUNX mRNA and VEGF mRNA in pleural fluid for differentiating benign from malignant origin.

OBJECTIVE: The purpose of this study was to evaluate the diagnostic utility of lung-specific X protein (LUNX) mRNA and vascular endothelial growth factor mRNA in differentiating pleural effusion of different origin. METHODS: A total of 136 patients with pleural effusion (46 cases of malignant pleural effusion caused by lung cancer, 30 cases of malignant pleural effusion caused by other cancers and 60 cases of benign pleural effusion) were enrolled in this study. Levels of LUNX mRNA and vascular endothelial growth factor mRNA in pleural fluid were detected by real-time quantitative polymerase chain reaction. Pleural fluid carcinoembryonic antigen and Cyfra21-1 were also measured simultaneously. RESULTS: The LUNX mRNA level was significantly higher in malignant pleural effusion caused by lung cancer than in malignant pleural effusion caused by other cancers and in benign pleural effusion. In malignant pleural effusion caused by cancers of different origin, the vascular endothelial growth factor mRNA level was significantly higher than in benign pleural effusion. For the diagnosis of malignant pleural effusion caused by lung cancer, LUNX mRNA exhibited higher sensitivity (80%), when compared with vascular endothelial growth factor mRNA (65%), carcinoembryonic antigen (67%) and Cyfra21-1 (61%), with the same specificity (95%). The combination of LUNX mRNA and cytology achieved a sensitivity of 85%. The combined use of LUNX mRNA and vascular endothelial growth factor mRNA and cytology raised the sensitivity to 89%, with 95% specificity. In initial cytology-negative pleural effusion from lung cancer, LUNX mRNA achieved the highest positive result (65%) among the four markers. CONCLUSIONS: The detection of LUNX mRNA and vascular endothelial growth factor mRNA in pleural fluid may be a complementary tool for the diagnosis of malignant pleural effusion. In particular, pleural fluid LUNX mRNA provided a valuable adjunct in distinguishing malignant pleural effusion caused by lung cancer from benign pleural effusion.

Significance of combined detection of LunX mRNA and tumor markers in diagnosis of lung carcinoma.

OBJECTIVE: To evaluate the significance of combined detection of LunX mRNA, carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), and cytokeratin 21-1 fragment (CYFRA21-1) in clinical diagnosis of lung carcinoma. METHODS: Based on the quantitative RT-PCR and chemiluminescence immunoassay, the expression levels of LunX mRNA, CEA, NSE, and CYFRA21-1 in 113 patients with lung carcinoma (case group) and 30 healthy participants (control group) were detected. Meantime, the sensitivity, specificity, and accuracy of the combination detection were also explored. RESULTS: The positive rates of LunX mRNA in peripheral blood and CEA, NSE, and CYFRA21-1 in serum were significantly higher in case group than those in control group ((χ) (2)=17.295, 16.825, 19.148, and 17.450; P<0.05). There was no statistical significance when positive rate of LunX mRNA was evaluated among different pathological types ((χ) (2)=0.047, P>0.05). The positive rate of LunX mRNA in stage I + II, III, and IV had a significantly increasing tendency ((χ) (2)=10.565, 32.462, P<0.05). The positive rate of CYFRA21-1 was highest in squamous carcinoma (78.5%), the positive rate of NSE was highest in small cell carcinoma (86.7%), and the positive rate of CEA wag highest in lung adenocarcinoma (80.4%). The sensitivity and accuracy of the combination detection were 91.1% and 88.1%, respectively. CONCLUSIONS: The combined detection of LunX mRNA and tumor markers (TMs) including CEA, NSE, and CYFRA21-1 in peripheral blood is helpful to increase the diagnostic accuracy of lung cancer. Also, it can inform the pathological typing of lung carcinoma.