The use of immunoperoxidase panels for the cytologic diagnosis of malignancy in serous effusions

Abstract

The diagnostic value of an immunoperoxidase panel composed of antisera to carcinoembryonic antigen (CEA), epithelial membrane antigens (EMA), and high- and low-molecular-weight cytokeratins was evaluated on 39 consecutive pleural and peritoneal fluid specimens and correlated with routine cytologic and histochemical studies. The cases were classified into two groups: malignant (epithelial and small-cell undifferentiated carcinomas) and benign effusions. We found that the CEA and EMA antisera identified 91% and 100% of the epithelial malignancies, respectively. Mucin stains were positive in only 41% (mucicarmine) and 59% (Alcian blue) of these cases. The battery of cytokeratin markers identified malignant cells from 45%-100% of the cases but showed considerable positive staining of mesothelial cells. A selective review of the literature is presented along with recommendations for technical improvement in immunoperoxidase studies. We believe that an immunoperoxidase panel can be of considerable value in the cytologic diagnosis of epithelial malignancies in effusions. The panel composed of CEA and EMA can prove helpful in a routine cytology practice. Although the cytokeratin marker identified malignant cells, the concomitant immunostaining of mesothelial cells limits its utility. The commercially available panel can be a potential aid in improving the accuracy of serous fluid cytologic examination by decreasing both false-positive and false-negative diagnoses and thereby helping to prevent delays in diagnosis and treatment.

Ber-EP4 for Differentiating Adenocarcinoma from Reactive and Neoplastic Mesothelial Cells in Serous Effusions

“…4,9,10,19 Previous investigations have shown Ber-EP4 immunopositivity to be relatively sensitive and specific for adenocarcinomas in cytologic material. 2,3,5,6,10,17,18 Our study strongly supported this conclusion. However, in contrast to studies that found a 6-13% false positive rate in benign mesothelial cells from peritoneal fluid from women and 11-15% from mesotheliomas, 3,6,10 specificity in our study was 100%.…”

“…7,15 Preliminary studies suggest that this antibody may also be of diagnostic utility in cytospin specimens. 2,3,5,6,10,17,18 This study was designed to evaluate the efficacy of this marker in identifying adenocarcinomas in routine cytologic preparations and to compare the results with those of other antibodies currently in use, including CEA, B72.3 and Leu-M1, with particular regard to the pattern of immunoreactivity and ease of interpretation.…”

“…10,17,20 Leu-M1 (CD 15) also stains granulocytes specifically and has lower sensitivity, 30-40%. 14,20 B72.3 often stains adenocarcinomas focally, as shown in the current study, and has variable sensitivity and specificity, the latter ranging from 0% to 11%.…”

Immunohistochemical Panel for Distinguishing Between Carcinoma and Reactive Mesothelial Cells in Serous Effusions

“…Nonspecific CEA staining of monocytic cells occurs because of the cells' expression of a blood group glycoprotein sharing antigenicity with CEA. 26 This inherent nonspecificity was apparent in our study because background staining of inflammatory cells was present.…”

Increased Natural Killer Cells in Fluids

“…Each method has been successful, with limitations in sensitivity and specificity. [1][2][3][4][5][10][11][12][15][16][17]18,20,[23][24][25] In the past, lymphocyte subtyping has been examined in fluids, including malignant effusions, but more recently, 4,5 little emphasis has been placed on the use of lymphocyte subtyping of inflammatory infiltrates in association with malignant or reactive processes. The role of the natural killer (NK) cell in effusions has not been investigated by flow cytometry.…”