A preliminary estimation of tissue factor pathway inhibitor (TFPI) and protein C in patients with intracranial tumors

Background. In patients with intracranial tumors, hypercoagulability is observed due to brain tissue and tumor cells being the source of tissue factor. Objectives. The aim of the study was to assess tissue factor (TF), tissue factor pathway inhibitor (TFPI) and protein C in the plasma and tumor tissue homogenate in patients with intracranial tumors. Material and methods. The study included 77 patients; 24 patients were diagnosed with glioma, 20 patients with meningioma and 33 patients with metastatic tumors; mean age - 54 years. The material for the study was the plasma and tumor tissue homogenate sampled during surgery. The control group consisted of 30 controls; mean age - 51 years. In the plasma of all the participants and in tumor tissue homogenate, the concentrations of TF-Ag, TFPI-Ag and protein C activity, and the concentration of total protein were measured. The results were converted per mg of protein. Results. In patients with intracranial tumors, elevated concentrations of TF-Ag, TFPI-Ag and protein C activity were noted, also after the conversion per mg of protein. A 100-fold higher concentration of TF per 1 mg of protein was found in tumor tissue compared to the patients' plasma. In tumor tissue homogenate, a lower TFPI concentration and a lower protein C activity were recorded. Conclusions. The study confirmed the essential prothrombotic properties in patients with intracranial tumors, expressed with an elevated TF level, as well as a tremendous amount of TF in tumor tissue homogenate derived from tumors. The elevated concentration of TFPI and protein C activity converted per mg of total protein should be analyzed in terms of their pleiotropic function, along with the participation in hemostasis control. It seems that the reduced protein C activity and low TFPI level are associated with the enormous TF value in tumor tissue homogenates.