A CASE OF MALIGNANT HEMANGIOPERICYTOMA - AN IMMUNOHISTOCHEMICAL AND ULTRASTRUCTURAL-STUDY

We report one case of malignant hemangiopericytoma which started with a tumor in the lower jaw and multiple nodules in the lung. The tumor q uickly metastasized to the brain and chemotherapy was not at all effec tive. Hemangiopericytoma is generally diagnosed by its histological ch aracteristics. Recently, however, electron microscopy and immunohistoc hemical methods have been used for its diagnosis. In our case, electro n micrograph showed the growth of hemangiopericytoma cells around imma ture endothelial cells. In addition, the tumor cells reacted positivel y only with antivimentin antibodies, and the endothelial cells in the tumor tissue were positive for antifactor VIII antibodies. The observe d features were consistent with the characteristics of hemangiopericyt oma.