Abstract: Objective: To research the effect and the prognostic assessment of VEGF in malignant pleural effusion, as well as the usefulness of VEGF in differential diagnosis between benign and malignant effusion. Methods： Using the sandwich enzyme-linked immunosorbent assay(ELISA), we detected the level of VEGF, carcinoembryonic antigen(CEA)and adenosine deaminase(ADA)in effusion and plasma respectively in pulmonary carcinoma(n=32), tuberculous(n=34) and transudative(n=9). Results: The level of VEGF in effusion and plasma in patients with pulmonary carcinoma（345±167ng/l and 120±79ng/l）was significantly higher than that in patients with tuberculous（119±52ng/l and 53±20ng/l）and transudative（57±22ng/l and 35±12ng/l）（P＜0.05）; the level of VEGF in tuberculous was higher than that in transudative（P＜0.05）; the level of VEGF in pulmonary carcinoma patients with malignant effusion whose survival time was shorter than six months（386±185ng/l）was evidently higher than that in those who survived longer than twelve months（201±88ng/l）（P＜0.05）.VEGF level was positively correlated with CEA and LDH level（r=0.51,r=0.46, P＜0.01）and not correlated with ADA level, glucose, protein content, the total number of WBC and classified count（P＞0.05）.The VEGF level in pleural effusion provided a diagnostic test for malignancy with a sensitivity of 75.6% and a specificity of 73.5%(cut-off point 221ng/L）. Conclusion： VEGF plays an important role in the malignant pleural effusion accumulation and is related to prognosis. The measurement of VEGF is helpful in discriminating between benign and malignant effusion.

Key words: Pleural effusiion, malignant, Tuberculosis, meningeal, Vascular endothelial growth factor