['ESSENTIALS: Cancer patients are at high risk of venous thromboembolism (VTE). In this study, cases and controls were cancer patients who did or did not develop VTE. von Willebrand factor (VWF) levels were higher if compared with controls and correlated with cancer stage. VWF and ADAMTS-13 are associated with the occurrence of VTE in cancer.', 'Patients with cancer are at high risk of venous thromboembolism (VTE). ADAMTS-13 regulates von Willebrand factor (VWF) activity, which plays a role in the development of cancer and in VTE.', 'The aim of this study was to search for an association between the levels of VWF and ADAMTS-13 and VTE in patients with cancer and to compare current scoring systems for prediction of VTE before and after addition of these parameters.', 'In a case-control study, in which patients with recently diagnosed cancer were followed-up for 6 months, we compared 20 patients who developed VTE (cases) and 140 patients with cancer without VTE (controls), matched for sex, age, and type and stage of cancer. We measured VWF, ADAMTS-13 (activity and antigen), P-selectin, D-dimer and F1 + 2 levels at baseline, and calculated both the Khorana score and the Khorana score expanded after addition of P-selectin and D-dimer levels.', 'VWF levels were significantly higher in cases when compared with controls (326 ± 185% vs. 242 ± 158%) and correlated with advanced stage of cancer: localized, 185 [142; 222]; locally advanced, 240 [146; 257]; metastatic, 267 [153; 324] (mean [interquartile range]). The addition of two biomarkers, ADAMTS-13 activity and F1 + 2 levels, to the Khorana score improved receiver operating curves.'] Do aDAMTS-13 and von Willebrand factor predict venous thromboembolism in patients with cancer?