Low-Molecular-Weight Heparin vs. Oral Vitamin K Antagonist for Cancer-Associated Venous Thromboembolism

Abstract This chapter examines the CLOT trial, which compares the efficacy of low-molecular-weight heparin (LMWH) and oral vitamin K antagonists (VKAs) for treating cancer-associated venous thromboembolism (VTE). The study showed that LMWH reduces recurrent VTE more effectively than VKA without increasing the risk of major bleeding. Patients treated with LMWH experienced fewer recurrent VTE episodes, and both groups showed similar mortality rates, primarily resulting from cancer-related causes rather than anticoagulation therapy. While LMWH proved superior in preventing recurrent VTE, the chapter highlights challenges in managing international normalized ratio levels with VKAs. It concludes that when choosing an anticoagulant for cancer-associated VTE, one should consider individual patient characteristics, with direct oral anticoagulants now recommended in some clinical guidelines.