[Pathologic study of pleural and peritoneal mesotheliomas of rats induced by asbestos].

Forty-six cases of mesotheliomas of rats induced by asbestos, 2 cases of human mesotheliomas and 10 cases of adenocarcinomas were studied by light microscopy, electron microscopy, histochemical and immunohistochemical staining. The results indicated that mesothelioma probably originates from the multipotential subserosal cell which has the features of myofibroblast. In addition to the epithelial, fibrous and mixed types of mesothelioma classified by WHO, poorly differentiated type of mesothelioma can also be found in rats. Electron microscopy, histochemical and immunohistochemical staining are very helpful in differentiating mesotheliomas from adenocarcinomas.