Increased microparticle tissue factor activity in cancer patients with Venous Thromboembolism

Cancer patients exhibit a high rate of thromboembolism (VTE). In this study, we analyzed levels of microparticle (MP) tissue factor (TF) activity in cancer patients with or without VTE. Blood was collected from cancer patients within 24 h of objectively diagnosed VTE (n=53) and from cancer patients without VTE (n=13). MPs were isolated from platelet poor plasma by centrifugation at 20,000g for 15 min. MP TF activity was measured using a two-stage chromogenic assay. Cancer patients with VTE had a significantly higher mean MP TF activity compared with cancer patients without VTE (1.7 +/- 3.8 pg/mL vs 0.6 +/- 0.4 pg/mL, p<0.05). Further prospective studies are required to determine if levels of MP TF activity may be a useful biomarker to identify patients at increased risk for VTE. (C) 2009 Elsevier Ltd. All rights reserved.