[Efficacy and safety of non-vitamin K antagonist versus vitamin K antagonist oral anticoagulants in the prevention and treatment of thrombotic disease in active cancer patients: a systematic review and meta-analysis of randomized controlled trials].

Object We aimed to compare the efficacy and safety of non-vitamin K antagonist oral anticoagulants (NOAC) and vitamin K antagonist (VKA) in the prevention and treatment of thrombotic diseases in patients with active cancer. Methods: To find randomized controlled trials (RCT) in which NOACs were compared VKAs in active cancer, we searched the electronic databases (PubMed, Web of Science and Clinical Trials) up to May 2019 and and languages restricted to Chinese and English. According to the screening strategy, two researchers independently screened and extracted literature, evaluated the quality of literature, the suitability of collected cross study data for analysis, and tested the heterogeneity. The relative risk (RR) and 95% confidence interval (95%CI) of major bleeding, clinically related non-major bleeding, VTE, stroke and all-cause mortality in active cancer patients with VTE, active cancer patients with non-valvular atrial fibrillation (NVAF) was calculated and the results were compared between NOAC with VKA. Results: A total of 9 RCTs were included, including 5 cancers with VTE (5/9) and 4 cancers with NVAF (4/9). A total of 5 867 patients were included. After excluding 1 818 (30.99%) patients with cancer history, 4 049 (68.86%) patients with active cancer were statistically analyzed. Among them, 2 278 (56.26%) received NOAC treatment, 1 771 patients (43.74%) received VKA treatment. The quality of the included documents was high (all scores were>5 points), and the data of each included document could be summarized and analyzed (P>0.05). The heterogeneity of main outcome events was very low (I2 = 0). In VTE patients with active cancer, NOACs were more effective in reducing recurrence of VTE （RR=0.55, 95%CI 0.36 -0.84; P = 0.005) and clinically related non-major bleeding (RR=0.77, 95%CI 0.60 -0.98; P = 0.03) than VKAs. In NVAF patients with active cancer, efficacy of NOACs and VKAs was similar in terms of reducing VTE, stroke, clinically related non-major bleeding, major bleeding and all-cause mortality events (P>0.05). Conclusions: For patients with active cancer accompanied by VTE, NOAC may has more advantages in efficacy and safety compared to VKA in the prevention and treatment of thrombotic diseases.