Efficacy and safety of novel oral anticoagulants for the treatment of cancer-associated venous thromboembolism: protocol for an umbrella review of systematic reviews and meta-analyses.

INTRODUCTION:Novel oral anticoagulants (NOACs) have been used in antithrombotic therapy in patients with cancer, and their efficacy and safety have been evaluated in several meta-analyses. Although a large body of findings has accumulated to support the benefit of NOACs for the treatment and prevention of cancer-associated thromboembolism, there is no convincing evidence because of inconsistent results across studies and questionable data quality. Its efficacy and safety remain controversial, especially with regard to the risk of bleeding. METHODS AND ANALYSIS:We will search PubMed, Embase and Web of science, Cochrane Library on 19 April 2022 (searches will be updated until complete) to identify systematic reviews, meta-analyses and pooled analyses of the efficacy and safety of NOACs for the treatment of cancer-associated venous thromboembolism. The quality of eligible systematic evaluations will be measured by A Measurement Tool to Assess Systematic Reviews. For each outcome, if a random effects model is not used, we will extract the data and estimate a 95% CI using the random effects model approach. For each random effects estimate, a 95% prediction interval is calculated. Heterogeneity between studies will be quantified using the I2 metric. In addition, if an assessment contains at least three articles, we will reanalyse the assessment using Egger's asymmetry test to detect and visualise possible publication bias in the articles. ETHICS AND DISSEMINATION:No formal ethical approval is required since we will use publicly available data. We will disseminate the findings of the umbrella review through publication in a peer-reviewed journal and conference presentations. PROSPERO REGISTRATION NUMBER:CRD42022342053.