Glyco- and immunohistochemical refinement of the differential diagnosis between mesothelioma and metastatic carcinoma and survival analysis of patients

The aim of this study was to analyse the diagnostic value of selected glyco - and immunohistochemical probes for discrimination between mesotheliomas a nd metastatic carcinomas within the pleura, and to evaluate prognostic indi cators in the tested panel. A panel of nine markers (five antibodies, two n eoglycoproteins. and labelled hyaluronic acid) a as applied to a total of 2 64 specimens with mesotheliomas (118 cases) and metastatic carcinomas in th e pleura (146 cases); the material consisted exclusively of surgical specim ens. The diagnosis obtained by standard procedures was further substantiate d through a detailed follow-up and clear-cut descriptions of primary sites, The metastatic tumours originated from the lung (82 cases), breast (47 cas es), colon (three cases), and kidney (two cases): in 12 cases, however, the tumour origin could not be ascertained. In detail, the probes tested inclu ded antibodies against carcinoembryonic antigen (CEA), vimentin, calretinin , mesothelial cells (HBME-1), calcyclin and keratin-5; and also biotinylate d neoglycoproteins with ganglioside GMI and N-acetyl-D-glucosamine (GlcNAe) as the ligand part, and hyaluronic acid. Carrier-immobilized ganglioside G MI and hyaluronic acid displayed the highest specificity and sensitivity fo r mesotheliomas, followed by calretinin and HBME-1, whereas keratin-5 and v imentin were of low specificity (43% and 52%, respectively), Metastatic car cinomas could be discerned by CEA detection and application of GlcNAc-beari ng neoglycoprotein with similar sensitivity (76% and 72%, respectively) and specificity (91% and 86%, respectively), In cases of breast carcinoma, the maximum specificity (59%) and sensitivity (67%) were low for all markers. Patients with mesothelioma survived longer than those with metastatic carci noma, especially those with detectable binding sites for hyaluronic acid. N o association of tumour type and binding properties of the other applied pr obes with survival of the patients could be found at a statistically signif icant level. It is concluded that in routine practice, the application of c arrier-immobilized CMI, hyaluronic acid, and antibodies against calretinin and HBME-1 is useful for confirmation of mesothelioma. whereas the detectio n of CEA and GlcNAc-specific binding sites is useful for distinguishing met astatic carcinoma from mesothelioma. Despite the rather infrequent occurren ce of mesotheliomas in women, particular attention should be given to exclu de or confirm metastatic breast carcinoma in cases of unknown history or lo ng metastatic interval. Copyright (C) 2000 John Wiley & Sons, Ltd.