Abstract
Sections of various adenocarcinomas and malignant mesotheliomas were tested for carcinoembryonic antigen (CEA) localized in tissues by the immunoperoxidase technique; epithelial mucin was demonstrated with the PAS technique. While CEA and mucin were found in many adenocarcinomas, both were absent in the 43 cases of malignant mesothelioma we investigated.
In the problem of distinguishing between adenocarcinoma and mesothelioma, the CEA-test in combination with conventional stains for mucin is a useful technique and clearly identifies most adenocarcinomas. A dual negative result for CEA and mucin, although not proving that a given lesion is a mesothelioma, adds considerable support to this histological diagnosis.