Management of Cancer-Associated Thrombosis

Low molecular weight heparin (LMWH) has been the standard of care for patients with cancer-associated thrombosis (CAT) for over 10 years; however, its adoption has been limited. The appearance of direct acting oral anticoagulants (DOACs) revolutionized the treatment of non-cancer venous thromboembolism (VTE) through their attractive fixed dose regimens; however, a lack of dedicated trial experience had relegated their position to off-label use in patients with cancer. The goal of this review is to review the evidence that has been generated over the last 3 years for factor Xa inhibitors, summarize their current position in the guidelines, and highlight areas of ongoing uncertainty with respect to the management of CAT. Four dedicated trials of patients with CAT have been published comparing edoxaban, rivaroxaban, or apixaban with the LMWH, dalteparin. While these trials all have differences in sample size and inclusion/exclusion criteria, the totality of evidence suggests these agents have similar (if not superior) efficacy for reducing the risk of VTE recurrence without a significant excess in major bleeding. These overall favorable results have translated to guideline recommendations with caveats for patients at high bleeding risk or those with anticipated drug-drug interactions. Direct-oral anticoagulants now feature prominently in the treatment guidelines for patients with CAT. These agents are, however, not for everyone and ongoing research will need to identify which patients are most, and least likely to benefit from a DOAC-based regimen, and the optimal duration. Furthermore, the incorporation of these data with emerging results from patient-preference research is required to personalize decisions in these patients.