Immunocytochemistry and DNA-image cytometry in diagnostic effusion cytology. II. Diagnostic accuracy in equivocal smears

To determine sensitivity and specificity of different antibodies for the im munocytochemical detection of malignant cells in diagnostically equivocal e ffusions in comparison with those achieved by DNA-image cytometry. 65 cytologically doubtful effusions of the serous cavities were stained wit h twelve antibodies. Furthermore, DNA-image cytometry was performed. Data w ere correlated with patient follow-up. Sensitivity of cellular staining of Ber-EP4 for the identification of malig nant cells was 77.8%, specificity of absent staining for benign cells was 1 00%. Positive predictive value for the identification of malignant cells wa s 100%, negative value 65.5%. Sensitivity of DNA-aneuploidy for the identif ication of malignancy was 82.9%, specificity of DNA-non-aneuploidy for beni gnity 94.7%. The positive predictive value of DNA-aneuploidy for the occurr ence of malignant cells was 96.7%. Negative predictive value of DNA-non-ane uploidy was 72.0%. Combining immunocytochemistry applying Ber-EP4 only and DNA-cytometry in equivocal effusions resulted in a sensitivity of 88.9% for the identification of malignant cells associated with a 95.0% specificity. Positive predictive value was 97.7%, the negative one 79.2%.