Introduction: Pleural effusion is a common clinical problem with management difficulties. The aim of this study is to evaluate vascular endothelial growth factor (VEGF) in differential diagnosis of pleural effusions and the presence of correlation between radiological features and biochemical properties.
Materials and methods: The study included patients with pleural effusion. VEGF levels in the pleural fluid were measured by enzyme-linked immunosorbent assay.
Results: A total of 97 patients who had exudative pleural effusion related to lung cancer (n = 17), nonpulmonary malignancies (n = 25), mesothelioma (n = 9), pneumonia (n = 14), tuberculosis (n = 8), miscellaneous causes (n = 6), and transudative effusion (n = 18) were included. Pleural VEGF levels were higher in exudative effusions with respect to transudative effusions (P < 0.001) and in effusions related to malignancies versus benign causes (P < 0.001). Pleural VEGF was inversely correlated with pleural fluid glucose and pH levels and had positive correlation with lactate dehydrogenase, protein levels (P < 0.001), hematocrit, and eosinophil values in the pleura (P < 0.05). Pleural VEGF levels were also higher in patients with massive effusions and pleural thickening (both P < 0.001).
Conclusions: The overlap of pleural VEGF levels between the groups may limit the value of VEGF in discriminating between malignant versus benign and exudative versus transudative effusions; however, it may be a useful adjunct to various methods. The VEGF levels in pleural fluid seem to be related to the degree of inflammation and pleural invasion.