What’s the best VTE treatment for patients with cancer?
EVIDENCE-BASED ANSWER:
No head-to-head studies directly compare all the main treatments for venous thromboembolism (VTE) in cancer patients. Long-term treatment (3-12 months) with low-molecular-weight heparin (LMWH) reduces recurrence of VTE by 40% compared with vitamin K antagonists (VKA), but doesn’t change rates of mortality, major or minor bleeding, or intracranial hemorrhage in patients with solid or hematologic cancer at any stage or in any age group. Initial treatment with LMWH reduces mortality by 30% compared with unfractionated heparin (UFH) for 5 to 10 days followed by warfarin, but doesn’t alter recurrent VTE or bleeding. Non-vitamin K oral anticoagulants (NOACs) have risks of recurrent VTE or VTE-related death (composite outcome) and clinically significant bleeding comparable to VKA or LMWH/VKA (strength of recommendation [SOR]: B, meta-analyses of randomized controlled trials [RCTs], mostly of low quality).
Non-vitamin K oral anticoagulants vs LMWH/VKA or VKA: No differences
A meta-analysis of RCTs comparing NOACs (dabigatran, edoxaban, apixaban, rivaroxaban) with VKA for 6 months found no differences in recurrent VTE or major bleeding.2
A second meta-analysis of RCTs that compared NOACs (rivaroxaban, dabigatran, apixaban) with control (LMWH followed by VKA) in adult cancer patients (mean ages, 54-66 years; 50%-60% men) reported no difference in the composite outcome of recurrent VTE or VTE-related death nor clinically significant bleeding over 1 to 36 months (most RCTs ran 3-12 months).5 Separate comparisons for rivaroxaban and dabigatran found no difference in the composite outcome, and rivaroxaban also produced no difference in clinically-significant bleeding.
RECOMMENDATIONS
The 2016 CHEST guidelines recommend LMWH as first-line treatment for VTE in patients with cancer and indicate no preference between NOACs and VKA for second-line treatment.6
