Vimentin, carcinoembryonic antigen and keratin in the diagnosis of mesothelioma, adenocarcinoma and reactive pleural lesions.

An immunohistochemical study of reactive pleural lesions, adenocarcinomas and mesotheliomas using carcinoembryonic antigen (CEA), cytokeratin and vimentin was carried out. All the specimens were obtained at surgery except for 11 mesotheliomas found at necropsy. Vimentin was positive in 23 of 27 mesotheliomas and negative in all the adenocarcinomas and 4 of 17 reactive mesothelial lesions. Conversely, CEA was positive in all the adenocarcinomas but negative in all mesotheliomas. Immunoreactivity for vimentin was seen in only 3 of 11 post-mortem mesotheliomas. Vimentin is a useful adjunct to the tissue diagnosis of mesothelioma especially when CEA is negative and cytokeratin positive. Its use appears largely confirmed to well fixed surgically derived tissues.