Study On Pathological Changes And Ultrastructure Of Stereotactic Poly-target Biopsy Specimens Obtained From Peritumoral Edema Area In Intracranial Tumors

Objective: In order to demonstrate the nature and pathogenesis of perituraoral edema area(PTEA) in intracranial tumor.Methods: PTEA was classified for three classes:first class 0-20mm, second class21-40mm, third class>40mm. The pathological characteristics and ultrastructure in this area by stereotactic poly-target biopsy of 22 patients with various intracranial tumors were studied with light and electron microscope.Results:Infiltrating tumor cells were noted in peritumoral brain edema area in specimens of astrocytomas, germinoma , malignant lymphoma and metastatic tumors. Furthermore,tumor cells were concentrated in a range of 20mm in the PTEA, the shape of these tumor cells was similar to the tumor body's . As to 15 Astrocytomases ,it was found that the more malignant of tumor and serious of PTEA, the more wide of the tumor cell infiltrating. No tumor cells could be seen in peritumoralregion in specimens of meningioma and craniopharyngioma, the boundary of tumor body and PTEA was clear. The distribution and structural changes of tumorous ' and peritumoral capillaries were found to affect the shape of peritumoral edema areas. In general marked abnormality of tumorous capillary ultrastucture offen appeared in those cases with large peritumoral edema areas. Some of the peritumoral neuroglial cells and capillary endotheliocytes exhibited moderate intracellular edema. Swollen mitochondria might be seen in many neuroglial cells.Conclusions: There is no tumor cells could be seen in the peritumoral ' edema area of meningioma an'd craniopharyngioma. However, the corresponding area in astrocytomas, germinoma , malignant lymphoma and metastatic tumors is extension of tumor accompanied by edema. The intracranial tumor body and PTEA all have a different change in capillary ultrastructure, both of them bring about the PTEA.