Diagnostic value of biochemical biomarkers in malignant and non-malignant pericardial effusion

The aim of this study was to examine the biochemical composition of pericardial effusions of different etiology and to evaluate the diagnostic utility of biochemical parameters and tumor markers to discriminate malignant from benign effusion. Pericardial and serum levels of biochemical parameters and tumor markers were compared in 105 patients who underwent pericardiocentesis and pericardioscopy with targeted epicardial biopsy. Etiologic diagnosis was based on pericardial fluid and epicardial biopsy analysis by cytology, histology, immunohistochemistry, microbiology and polymerase chain reaction. The total of 105 patients comprised 29 patients with malignant and 76 patients with non-malignant pericardial effusions (40 autoreactive, 28 viral, 5 postcardiotomy syndromes and 3 associated with systemic diseases). Malignant pericardial effusions had significantly higher pericardial fluid levels of the tumor markers CEA, CA 19-9, CA 72-4, SCC and NSE (p < 0.001, p = 0.002, p < 0.001, p = 0.004 and p < 0.001, respectively) as well as higher pericardial fluid hemoglobin (p < 0.001), pericardial fluid white blood cells (p = 0.003), pericardial fluid LDH (p < 0.001) and ratio of pericardial to serum LDH levels compared to benign effusions. None of the biochemical or cell-count parameters tested proved to be accurate enough for distinguishing malignant from benign effusions. However, measurement of pericardial CA 72-4 levels offered a high diagnostic accuracy for malignancy, particularly in bloody pericardial effusions. None of the biochemical parameters tested was useful for the discrimination of malignant from benign effusions. However, measurement of pericardial CA 72-4 levels in bloody pericardial effusions yielded a high diagnostic accuracy and thus offers the potential as a diagnostic tool to distinguish between malignant and benign effusions.