Summary
A prothrombotic state is one of the hallmarks of malignancy and a major contributor
to morbidity and mortality in cancer patients. Tissue factor (TF) is often overexpressed
in malignancy and is a prime candidate in predicting the hypercoagulable state. Moreover,
increased number of TF-exposing microparticles (MPs) in cancer patients may contribute
to venous thromboembolism (VTE). We have conducted a prospective cohort study to determine
whether elevated TF antigen, TF activity and TF associated to MPs (MPs-TF) are predictive
of VTE and mortality in cancer patients. The studied population consisted of 252 cancer
patients and 36 healthy controls. TF antigen and activity and MPs-TF were determined
by ELISA and chromogenic assays. During a median follow-up of 10 months, 40 thrombotic
events were recorded in 34 patients (13.5%), and 73 patients (28.9%) died. TF antigen
and activity were significantly higher in patients than in controls (p<0.01) mainly
in patients with advanced stages, whereas no differences were observed for TF activity
of isolated MPs. We did not find a statistically significant association of TF variables
with the risk of VTE. Multivariate analysis adjusting for age, sex, type of cancer
and other confounding variables showed that TF activity (p<0.01) and MPs-TF activity
(p<0.05) were independently associated with mortality. In conclusion, while TF variables
were not associated with future VTE in cancer patients, we found a strong association
of TF and MPs-TF activity with mortality, thus suggesting they might be good prognostic
markers in cancer patients.
Keywords
Cancer - venous thromboembolism - tissue factor - microparticles - prognosis