Purpose: Patients with cancer are at increased risk of venous thromboembolism (VTE). Laboratory tests measuring the overall thrombophilic tendency might be useful to assess VTE risk. The aim of this study was to investigate thrombin generation, a key process in hemostasis, as predictor of cancer-associated VTE.
Patients and methods: The Vienna Cancer and Thrombosis Study (CATS) is a prospective observational cohort study of patients with newly diagnosed cancer or progression of disease after remission. The study end point is occurrence of objectively confirmed symptomatic or fatal VTE within a follow-up period of 2 years. Thrombin generation was measured with a commercially available assay.
Results: One thousand thirty-three patients with malignancies of the breast (n = 151), lung (n = 148), upper (n = 44) and lower gastrointestinal tract (n = 125), pancreas (n = 67), kidney (n = 34), prostate (n = 122), and brain (n = 134) or lymphoma (n = 126), multiple myeloma (n = 26), and other tumor types (n = 56) were observed for a median observation period of 517 days. VTE occurred in 77 patients (7.5%). Patients with elevated peak thrombin (defined as values ≥ 611 nM thrombin, representing the 75th percentile of the total study population) had an increased risk of VTE with a hazard ratio of 2.1 (95% CI, 1.3 to 3.3, P = .002) in multivariable analysis including age, sex, surgery, chemotherapy, and radiotherapy. The cumulative probability of developing VTE after 6 months was significantly higher in patients with elevated peak thrombin than in those with lower peak thrombin (11% v 4%; log-rank test: P = .002).
Conclusion: Measurement of thrombin generation may help identify patients with cancer at high risk of VTE.