[Focal fibrous mesothelioma of the pleura (a morphological study of 7 cases].

Seven focal pleural tumours are studied histochemically, immunohistochemically and electron microscopically (EM). A great variety of histological and EM structures was found: areas resembling fibromas, fibrous histiocytomas, hemangiopericytomas, etc. The EM signs of the abortive mesothelial differentiation were found in the tumour cells. The use of the term "localised fibrous mesothelioma" seems to be justified. It is necessary to distinguish morphologically diffuse mesothelioma and localised fibrous mesothelioma that possess different clinical course and prognosis.