Diagnostic Value of CEA in Pleural Fluid for Differential Diagnosis of Benign and Malign Pleural Effusion

The diagnostic value of tumor markers in pleural fluid is still the subject of debate. The aim of this work was to evaluate diagnostic value of carcinoembryonic antigen (CEA) in pleural fluid for differentiating malignant from non malign pleural effusion, and their additive value to cytological examination. Design: Prospective, case control study. Setting: Tertiary University hospital, Clinic for Lung Disease, Knez Selo. Patients: Eighty two patients with pleural effusion, forty one with malignant, and forty one with non malignant pleural effusion. Measurements and results: Levels of CEA in pleural fluid was measured by IRMA CEA methods, INEP Belgrade. Patients with lung cancer were found to have significantly higher CEA levels than patients with non malign pleural effusion. Using cut off values of 2.4 ng/ml, the sensitivity of marker was 78%, and specificity 95.1 % (CI 95%). The addition of CEA to cytology increase diagnostic rate from 68 to 85.3%. Conclusion: CEA may represent a helpful adjunct to cytology in order to include malignancy as probable diagnosis, thus guiding the selection of patients for more invasive procedures.