RESUMO
BACKGROUND: The aim of this study was to evaluate the value of tumour markers in the differential diagnosis of pericardial effusions and to assess their changing levels during follow up. METHODS: Sixty-nine patients who were admitted to hospital with a diagnosis of pericardial effusion were included in the study. Serum tumour markers were measured on admission and after a mean of 18 ± 7 months' follow up. An aetiological diagnosis was made on clinical evaluation, imaging techniques and biochemical, microbiological and pathological analysis. The patients were divided into five groups according to the aetiology of their pericardial effusions. RESULTS: Carbohydrate antigen (CA) 12-5 and CA 15-3, and carcinoembryonic antigen (CEA) levels were significantly higher in patients with malignancies than in those with viral/idiopathic pericarditis. With multivariate analysis, CA 15-3 levels were found to be the most significant determinant (p = 0.027). In the ROC curve analysis, CA 15-3 values above 25 U/ml predicted a malignancy with 71% sensitivity and 78% specificity. CONCLUSION: Tumour markers, particularly CA 15-3, may be useful in the differential diagnosis and prediction of malignancies in patients with pericardial effusion. In patients with viral/idiopathic aetiology, these serum tumour markers were slightly elevated in the acute phase, but after a mean of one year of follow up, their levels returned to normal, contrary to those with malignancies.