Correlation of tumor plasminogen activator with peritumoral cerebral edema. A CT and biochemical study.

Extracts from 15 human cerebral tumors were tested by a fibrin-plate plasminogen-dependent assay for levels of tumor plasminogen activator (TPA) activity. The TPA activity was correlated with the amount of perineoplastic edema as quantified on computerized tomography (CT) brain scanning. Analysis of the results showed a correlation coefficient of 0.72 when all tumors were included. Analysis of the nine tumors with the highest TPA levels showed a correlation coefficient of 0.96. One metastatic tumor had the highest level of TPA activity, equivalent to a pure 100-micrograms/ml solution of urokinase, and the greatest amount of cerebral edema on CT. Meningiomas generally had the next highest levels of TPA activity and edema, followed by astrocytomas of varying grades, which generally had the lowest level of TPA activity. However, three astrocytomas that had low TPA activity also had significant edema surrounding the tumor, indicating that more than one mechanism may be producing peritumoral edema. There was no correlation between tumor size and the amount of perineoplastic edema. These preliminary results suggest that TPA's may be involved in the production of perineoplastic cerebral edema and that treatment of patients with currently available plasminogen activator inhibitors may be successful in reducing peritumoral edema.