Diagnostic value of interleukine-6, transforming growth factor-beta 1 and vascular endothelial growth factor in malignant pleural effusions

SummaryStudy objectivesWe evaluate the accuracy of pleural interleukine-6 (IL-6), transforming growth factor-beta 1 (TGF-β1), and vascular endothelial growth factor (VEGF) levels for differentiating benign from malignant pleural exudates.Patients and methodsLevels of IL-6, TGF-β1, and VEGF were measured by ELISA in 103 patients with non neutrophilic (<50%) exudative pleurisy including both benign and malignant effusions. Pleurisies were splitted into benign and malignant according to the pathological diagnosis.ResultsThirty-nine benign (seven infections; 32 inflammatory diseases) and 64 malignant (34 extrathoracic tumors; 25 lung cancers; five mesotheliomas) pleural exudates were diagnosed by thoracoscopy. Pleural reticulo-monocyte count, protein Light's ratio and lactic dehydrogenase Light's ratio were significantly higher in malignant than in benign effusions (p<0.05, p<0.001 and p<0.001, respectively). The median (range) level of VEGF was significantly higher in malignant than in benign effusions (664.50pg/ml [10–40,143] vs 349pg/ml [10–8888]) (p<0.05). VEGF levels correlated with pleural LDH (r=0.41, p<0.0001), glucose (r=−0.30, p<0.01) and red cell count (r=0.57, p