Multivariable clinical-genetic risk model for predicting venous thromboembolic events in patients with cancer

BACKGROUND: Venous thromboembolism (VTE) is a leading cause of death among patients with cancer. Outpatients with cancer should be periodically assessed for VTE risk, for which the Khorana score is commonly recommended. However, it has been questioned whether this tool is sufficiently accurate at identifying patients who should receive thromboprophylaxis. The present work proposes a new index, TiC-Onco risk score to be calculated at the time of diagnosis of cancer, that examines patients’ clinical and genetic risk factors for thrombosis. METHODS: We included 391 outpatients with a recent diagnosis of cancer and candidates for systemic outpatient chemotherapy. All were treated according to standard guidelines. The study population was monitored for 6 months, and VTEs were recorded. The Khorana and the TiC-Onco scores were calculated for each patient and their VTE predictive accuracy VTEs was compared. RESULTS: We recorded 71 VTEs. The TiC-Onco risk score was significantly better at predicting VTE than the Khorana score (AUC 0.73 vs. 0.58, sensitivity 49 vs. 22%, specificity 81 vs. 82%, PPV 37 vs. 22%, and NPV 88 vs. 82%). CONCLUSIONS: TiC-Onco risk score performed significantly better than Khorana score at identifying cancer patients at high risk of VTE who would benefit from personalised thromboprophylaxis.