Intratumoral tissue factor expression and risk of venous thromboembolism in brain tumor patients.
BACKGROUND
Brain tumor patients have an increased risk of venous thromboembolism (VTE). An important role in cancer-related VTE has been suggested for tissue factor (TF), the main initiator of the coagulation cascade. We conducted a prospective cohort study to determine whether expression levels of TF in brain tumors are associated with future VTE.


METHODS
We immunohistochemically determined TF-expression in brain tumor specimens of 96 adult patients (8 low-grade and 82 high-grade gliomas, 6 embryonal tumors) that were included in the Vienna Cancer and Thrombosis Study (CATS). Each patient was prospectively followed until the occurrence of VTE and/or death within a period of two years or loss of follow-up.


RESULTS
Fifteen brain tumor patients (15.6%) developed VTE during follow-up. Seventy-seven brain tumors (80.2%) stained positive for TF. Staining was strong in 13 (13.5%), moderate in 64 (66.7%) and negative in 19 (19.8%) tumors. No statistically significant association between TF-expression (negative, focal, widespread) and the occurrence of VTE was found. The hazard ratio (HR) for VTE was 1.30 (95% confidence interval [CI]: 054 - 3.14, p=0.567) when patients with negative-, focal- and widespread TF expression were compared and not statistically significant. Also when tumors were categorized into two groups (focal/widespread versus negative TF-expression), the HR for future VTE was not statistically significant (HR: 1.45, 95% CI: 0.44 - 7.37; p=0.578). An association can still not be definitely excluded, as this study was underpowered.


CONCLUSIONS
Our data indicate that TF-expression levels in brain tumors are not strongly associated with future VTE.
Department of Medicine I, Medical University of Vienna, Vienna, Austria.
Johannes
J
Thaler
Matthias
M
Preusser
Cihan
C
Ay
Alexandra
A
Kaider
Christine
C
Marosi
Christoph
C
Zielinski
Ingrid
I
Pabinger
Johannes A
JA
Hainfellner
D001932:Brain Neoplasms / Q000097:blood / Q000378:metabolism* / Q000473:pathology; D005260:Female; D005910:Glioma / Q000097:blood / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009373:Neoplasms, Germ Cell and Embryonal / Q000097:blood / Q000378:metabolism / Q000473:pathology; D012307:Risk Factors; D013925:Thromboplastin / Q000096:biosynthesis*; D054556:Venous Thromboembolism / Q000378:metabolism*
D013925:Thromboplastin