[Morphology of experimental malignant hemangioendothelioma]

Various histological stains, histoautoradiography and electron microscopy were used to study the morphologic features of 77 malignant hemangioendotheliomas induced in CBA mice with subcutaneously injected 1,2-dimethylhydrazine. The histologic and cytologic structure of those tumors proved similar to those of malignant hemangioendothelioma in man. The ability of tumor cells to form vascular structures and degree of their neoplastic atypia were used to identify three types of neoplasia: "cavernous hemangioma" with cytologic signs of malignity and well- and poorly--differentiated malignant hemangioendotheliomas. Due to high rate of tumor development and inevitable growth in the renal capsule which makes tumor easy to detect at early stage, the model offers promise for evaluating morphogenesis of malignant hemangioendothelioma.