Epithelial Marker E-cadherin, Cea, Moc-31, Ber-ep4 And Ttf-1 And Mesothelial Marker Calretinin, Hbme-1 And Thrombomodulin In Serous Effusions With Metastatic Adenocarcinoma, Malignant Epithelial Mesothelioma And Hyperplasia Mesothelial Cells To Identify I

Background: The morphological changes of metastatic adenocarcinoma cells, malignant epithelial mesothelioma cells and reactive mesothelial cells in the serous effusions are mimic. Sometimes, a right diagnosis could not be made just on the cytological features. So some additional diagnostic methods are needed. Recently, immunocytochemistry becomes the major diagnostic and differential diagnostic method in the field of effusion cytology. Because of cross reactions between the mesothelial cells and metastatic adenocarcinoma cells, one or two kinds of antibody are not enough for the differentialdiagnosis. So a panel of antibodies is needed. Recently, new epithelial/adenocarcinoma cell markers , such as E-cadherin, MOC-31, Ber-EP4, TTF-1 and new mesothelial cell markers, including calretinin, HBME-1, thrombomodulin are using in the cytological practice. The use of these new antibodies helps to make more correct diagnosis. The aim of present study is in search of the most specific and sensitive markers and the best panel from these antibodies.Materials and Methods: Ninety-three effusion cytology cases (66 pleural fluid samples, 24 peritoneal fluid samples, 3 pericardial fluid samples) from 32 cases of reactive mesothelium, 6 cases of malignant mesothelioma, 55 cases of metastatic adenocarcinoma were evaluated in this study. The diagnosis of all cases was confirmed by histology or clinical data. Cell block was prepared for each case. Immunocytochemical staining was performed on the paraffin sections of cell blocks and SP (streptavidin-peroxidase) method was used for all of the antibodies except TTF-1 which used En Vision method.Results: The sensitivity of E-cadherin, CEA, MOC-31 and Ber-EP4 for adenocarcinoma was 85.5 %(47/55), 78.2%(43/55), 69.1%(38/55) and 76.4%(42/55), respectively. The specificity of E-cadherin, CEA, MOC-31 and Ber-EP4 for adenocarcinoma was 100%(38/38), 97.4%(37/38), 92.1%(35/38) and 86.8%(31/38),respectively. The sensitivity of TTF-1 for adenocarcinoma and pulmonary adenocarcinoma was 34.6%(18/52) and 61.5%(16/26), respectively. The specificity of TTF-1 for adenocarcinoma and pulmonary adenocarcinoma was 100%(38/38) and 92%(23/25), respictively. The sensitivity of calretinin, FEBME-1 and thrombomodulin for mesothelium was 81.6%(31/38), 78.9%(30/38) and 47.4%(18/38), respectively. The specificity of calretinin, HBME-1 and thrombomodulin for mesothelium was 87.2%(48/55), 21.8%(12/55) and 67.3%(37/55), respectively. The expression of E-cadherin, CEA, MOC-31, Ber-EP4, TTF-1 and calretinin had significant difference between adenocarcinoma and reactive mesothelial/mesothelioma cells (P<0.005). A significant difference of the expression of TTF-1 between pulmonary adenocarcinoma and non-pulmonary adenocarcinoma cells also was obtained (P<0.005). The expressions of thrombomodulin, FffiME-1 had no significant difference between adenocarcinoma and reactive mesothelial/mesothelioma cells(P>0.1).Conclusions: E-cadherin, CEA and calretinin should be the best panel for the differential diagnosis between mesothelial cells and metastatic adenocarcinoma cells in the serous effusions. TTF-1 should be added if metastatic adenocarcinoma from the lung or thyroid is considered. If the staining of calretinin is not satisfactory, another mesothelial cell marker, thrombomodulin should be added. If thematerial is permitted only for two antibodies, E-cadherin and calretininshould be the best choice.