Novel High-Sensitive D-Dimer Determination Predicts Chemotherapy-Associated Venous Thromboembolism in Intermediate Risk Lung Cancer Patients

Identification of patients in whom venous' thromboembolism (VTE) risk justifies thromboprophylaxis is a major challenge. We investigated the predictive value of a novel D-dimer assay in intermediate-risk lung cancer outpatients. Prechemotherapy D-dimer levels significantly predicted VTE with 70% accuracy and 11.0 hazard ratio (HR), independently of classic VTE risk factors, helping in identifying a subset of patients who might benefit from thromboprophylaxis. Introduction: We hypothesized that the use of a novel high sensitivity (HS) assay for D-dimer determination might ameliorate venous thromboembolism (VTE) risk prediction in intermediate risk lung cancer patients in whom chemotherapy could act as a trigger for VTE onset. Patients and Methods: Pretreatment HS D-dimer levels were retrospectively evaluated in 108 lung cancer outpatients using a novel automated latex enhanced turbidimetric immunoassay. All patients were at the start of a new platinum-based chemotherapy regimen and were classified as intermediate risk according to Khorana's assessment model. Patients were followed-up for a median period of 6.9 months. Results: Receiver operating characteristic (ROC) curves and corresponding Bayesian analysis showed that the best performance was obtained at a cutoff level of 1500 ng/mL, which resulted in a sensitivity of 81%, a specificity of 69%, a positive predictive value (PPV) of 31%, a negative predictive value (NPV) of 96%, and an accuracy of 70%. Patients with HS D-dimer levels above the cutoff had a worse VTE-free survival (60%) compared with those with levels below the cutoff (95%; P=.0001). Multivariate Cox proportional hazards survival analysis confirmed that pretreatment HS D-dimer levels were able to significantly predict VTE with a hazard ratio of 11(95% confidence interval, 2.62-46.2; P=.001), independently of classic VTE risk factors. Conclusions: The use of HS D-dinner determination prior to chemotherapy might allow for VTE risk stratification of intermediate risk cancer patients, helping in identifying those individuals who could benefit from thromboprophylaxis.