THE DIAGNOSTIC-VALUE OF CEA LEVELS IN ASC ITIC AND PLEURAL EFFUSIONS - A PROSPECTIVE-STUDY IN 724 PATIENTS

ln two successive phases of a prospective study, the authors compared the ability of ascitic and pleural fluid CEA levels and of conventiona l cytologic examination to discriminate between benign and malignant e ffusions. After an initial (learning) phase in 609 patients with known diagnosis, a cut-off level was set at 8.0 ng/ml that separated betwee n benign and malignant cases in this group with a sensitivity of 38 % and a specificity of 95 %. In the second (evaluation) phase with 106 p atients whose diagnosis was not known at the time of the tap, this dis criminative limit resulted in a sensitivity of 32 %, a specificity of 98 %, a positive predictive value of 95 %, and a negative predictive v alue of 49 %. Conventional cytology had a sensitivity of 35 % (learnin g phase) and 30% (evaluation phase), resp. As elevated CEA concentrati ons were found also in cytologically negative effusions from patients with malignant tumors, the sensitivity for the detection of a neoplast ic disease could be improved to 38 % by the combination of effusion fl uid CEA determination and cytology. This moderate gain of additional i nformation justifies the measurement of CEA in diagnostically difficul t cases as the determination of the antigen is simple and readily avai lable.