BACKGROUND: To analyze patients with diagnosis of benign or malignant diseases, in whose evolution develop pleural effusion, in which CEA measurement was questioned in relation to sensitivity and specificity in the differentiation of these two groups. METHODS: Prospective consecutive case series of the Department of Thoracic Surgery, Conceição Hospital, Porto Alegre, Brazil. From July 2000 to December 2001, 64 patients were subjected to clinical investigation in search for a pleural effusion aetiology. All patients underwent the following laboratory evaluation of pleural fluid: pH, LDH, proteins, density, glucose, differential cytology, bacterial culture, search for fungus and acid-fast bacilli, cytology, CEA determination and pleural biopsy. RESULTS: Patients with malignant etiologic diagnosis (n=26), had CEA results ranging from zero to 5000 ng/ ml, while benign cases results were from zero to 4.8 ng/ml. CEA level in malignant fluids was of 431 ± 1237 ng/ml (mean ± SE), significantly higher than benign fluids (1.1 ± 1.0 ng/ml; p< 0.001). Sensitivity, for a cut-off of 5 ng/ml, was 61.5% and specificity of 100%. CONCLUSION: We conclude that for patients with pleural effusion, CEA concentrations may represent an useful criteria to diagnosis.
Carcinoembryonic antigen; Pleural effusion; pleural malignancy; tumour marker
