Lowering the burden of cancer-associated venous thromboembolism Prevention is better than cure

Venous thromboembolism (VTE) is a common and serious complication in patients with cancer. Its incidence is rising due to the increasing number of cancer diagnoses and improved survival rates. Selecting the optimal treatment strategy for cancer-associated VTE is challenging, given the high risks of both recurrent VTE and bleeding complications. While primary thromboprophylaxis is effective, it remains underused in daily practice. The aim of this thesis was to evaluate clinical challenges in the management of cancer-associated VTE and to explore opportunities to improve patient care. Part I focuses on the management of cancer-associated VTE in daily clinical practice in the Netherlands, evaluating anticoagulant therapy, associated risks of recurrence and bleeding, barriers to the uptake of thromboprophylaxis, and the feasibility of direct discharge and home treatment for patients with cancer and acute pulmonary embolism. Part II explores strategies to improve VTE risk assessment by evaluating the association of genetic predisposition, tumor genomics, and biomarkers of intrinsic coagulation with cancer-associated VTE, with the ultimate aim of refining patient selection for primary thromboprophylaxis. Part III aims to improve the detection of catheter-related thrombosis by comparing diagnostic imaging modalities and evaluating whether systemic activation of the intrinsic coagulation pathway can serve as a marker for catheter-related VTE. Part IV focuses on early detection of cancer in patients presenting with unprovoked VTE and investigates innovative blood-based approaches, including platelet RNA sequencing and plasma proteomics.