What is the Clinical Significance of Transudative Malignant Pleural Effusion?

BACKGROUND: A few reports of transudative malignant effusion on a small number of patients have suggested the need to perform routine cytologic examination in all cases of transudative pleural effusion, whether encountered for malignancy or not. The purpose of this study was to investigate whether cytologic examination should be performed in all cases of transudative pleural effusion for the diagnosis of malignancy. METHODS: We performed a retrospective study of 229 consecutive patients with malignant pleural effusion, proven either cytologically or with biopsy. In patients with transudative pleural effusion, we reviewed medical records, results of transthoracic echocardiography, fiberoptic bronchoscopy, chest X-ray, chest CT scan, and ultrasonogram of the abdomen. These data were examined with particular attention to identifying whether or not the malignancy was suggested on chest X-ray, examining the involvement of the superior vena cava, great vessels, and lymph nodes, determining the presence of pericardial effusion, and observing the endobronchial obstruction. RESULTS: Transudative malignant pleural effusion was observed in seven (3.1%) of the 229 patients, and was caused either by the malignancy itself (6 patients) or by coexisting cardiac diseases (1 patient). All the patients showed evidence suggesting the presence of malignancy at the time of initial thoracentesis, which facilitated the decision of most clinicians on whether to perform cytologic examination for the diagnosis of malignancy. CONCLUSION: Therefore, in all cases of transudative pleaural effusion, no clinical implications indicating malignancy were found on cytologic examination.

Vascular endothelial growth factor in malignant and tuberculous pleural effusions

The purpose of this study is to assess the usefulness of soluble vascular endothelial growth factor (VEGF) in the effusions of patients with malignant and tuberculous diseases. Using a sandwich enzyme-linked immunoadsorbent assay, VEGF concentration was measured in malignant (n=17) and tuberculous (n=11) pleural effusions. Pleural biopsy, cytology or microbiological methods were used to make final diagnoses. Adenosine deaminase (ADA) levels in tuberculous pleural effusions were significantly higher than those in malignant pleural effusions. The median level of VEGF in patients with malignant effusions (median, 2418 pg/mL; range, 97-62103 pg/mL) was significantly higher than tuberculous effusions (median, 994 pg/mL; range, 44-3552 pg/mL). There were no significant differences in pleural VEGF levels in patients with different histological types of lung cancer. The VEGF level was not correlated with ADA, lactate dehydrogenase and total protein levels of pleural fluid. In conclusion, pleural VEGF levels in patients with malignant effusions were significantly higher than tuberculous effusions, and the measurement of pleural VEGF is helpful in discriminating between malignant and tuberculous effusions. Further studies are needed to determine the clinical value of VEGF as a tumor marker and a prognostic factor.

Vascular endothelial growth factor in malignant and tuberculous pleural effusions

The purpose of this study is to assess the usefulness of soluble vascular endothelial growth factor (VEGF) in the effusions of patients with malignant and tuberculous diseases. Using a sandwich enzyme-linked immunoadsorbent assay, VEGF concentration was measured in malignant (n=17) and tuberculous (n=11) pleural effusions. Pleural biopsy, cytology or microbiological methods were used to make final diagnoses. Adenosine deaminase (ADA) levels in tuberculous pleural effusions were significantly higher than those in malignant pleural effusions. The median level of VEGF in patients with malignant effusions (median, 2418 pg/mL; range, 97-62103 pg/mL) was significantly higher than tuberculous effusions (median, 994 pg/mL; range, 44-3552 pg/mL). There were no significant differences in pleural VEGF levels in patients with different histological types of lung cancer. The VEGF level was not correlated with ADA, lactate dehydrogenase and total protein levels of pleural fluid. In conclusion, pleural VEGF levels in patients with malignant effusions were significantly higher than tuberculous effusions, and the measurement of pleural VEGF is helpful in discriminating between malignant and tuberculous effusions. Further studies are needed to determine the clinical value of VEGF as a tumor marker and a prognostic factor.