Cancer-associated thrombosis (CAT) is a common complication in patients with malignancy. Although direct oral anticoagulants (DOACs) have emerged as a treatment option for CAT, there have not been head-to-head comparisons of these agents. We searched MEDLINE and EMBASE from inception to April 2020 for studies comparing the effect of different long-term anticoagulation strategies for venous thromboembolism (VTE) in patients with cancer. We performed a network meta-analysis comparing the antithrombotic strategies in the selected studies using random-effects model. We identified a total of 20 studies [9 randomized control trials (RCTs) and 11 subgroup analyses from other unique RCTs] with total of 6699 patients for inclusion in our analysis. There was no significant difference in recurrent VTE, all-cause death, major bleeding and clinically relevant non-major bleeding among DOACs. When DOACs were combined, recurrent VTE was significantly decreased in DOACs compared to low-molecular weight heparin (LMWH) and Vitamin K antagonist (VKA) [RR (95% CI) 0.75 (0.59-0.94); RR (95% CI) 0.51 (0.39-0.66), respectively] without significant increase in major bleeding or clinically relevant non-major bleeding. In patients with CAT, there was no significant difference in recurrent thrombotic event among different DOACs. Bleeding risk was comparable among all anticoagulation strategies. When DOACs were combined, DOACs were associated with a significant decrease in recurrent VTE with comparable bleeding risk to LMWH and VKA.
Keywords: Cancer associated thrombosis; Direct oral anticoagulant; Oral anticoagulant; Venous thromboembolism.