[Diagnostic value of carcinoembryonic antigen in pleural fluid (author's transl)].

Of 30 unselected patients with pleural effusion of unknown cause 17 were subsequently found to have malignant disease of the pleura. In 11 of the 17 patients the concentration of carcinoembryonic antigen (CEA) in the pleural effusion was elevated to 4-60 ng/ml. In all 13 patients with pleural effusion of non-malignant cause the CEA concentration was normal (0-2 ng/ml). While the specificity of CEA antigen was 100% in the diagnosis of malignant pleural disease, its sensitivity was only about 65%. Since low CEA values in pleural effusion thus cannot exclude malignant disease with certainty, histological assessment of the pleural disease should be practised in every case where tumour is suspected, if necessary via thoracoscopy or thoracotomy.