Tumor Oncogenic Expression in Malignant Effusions as a Possible Method to Enhance Cytologic Diagnostic Sensitivity:An Immunocytochemical Study of 87 Cases

The diagnostic ability of cytological preparations can be hampered by specimen inadequacy and the presence of representative cells, which may result in a diagnostic accuracy of only 70%. An immunocytochemical battery (ICC), which included anti-p53, anti-c-erbB-2, and B72.3 MoAbs, was used to enhance sensitivity in 87 specimens of body effusions. Thirty-six cases were positive for malignancy using conventional cytology. Forty cases were negative and 11 cases were inconclusive or had an equivocal diagnosis. Sensitivity was 65%, and there was a negative predictive value (NPV) of 62%. p53 was expressed in 50 cases (56%, sensitivity = 83%, NPV = 73%), and B72.3 MoAb was positive in 36 cases (37%, sensitivity = 66%, NPV = 64%). Forty-eight cases (56%) displayed reactivity with anti-c-erbB-2 (sensitivity = 75%, NPV = 63%). The authors concluded that application of an ICC panel of anti-p53, B72.3 and c-erbB-2 to complement conventional cytology increases sensitivity to 98% (P < .0005) with an NPV of 96% (P = .001).