Direct oral anticoagulants versus low-molecular-weight heparin for acute treatment of venous thromboembolism in patients with gastrointestinal cancer: A systematic review and meta-analysis

Abstract BackgroundThe association between gastrointestinal (GI) cancer and a high incidence of venous thromboembolism (VTE) is well known. Previous randomized controlled studies demonstrated that direct oral anticoagulants (DOACs) effectively treat cancer-associated VTE (CAT). However, some DOACs appeared to increase the risk of bleeding, particularly in patients with GI malignancies. Therefore, the current systematic review and meta-analysis was conducted to evaluate the safety and efficacy of DOACs in GI cancer-associated thrombosis.MethodsAll relevant studies that compared DOACs and low-molecular-weight heparin (LMWH) in GI cancer-associated thrombosis that were published before December 2020 were individually searched in two databases (MEDLINE and EMBASE) by two investigators. The effect estimates and 95% confidence intervals (CI) from each eligible study were combined using the Mantel-Haenszel method.ResultsA total of 1,418 patients were included in this meta-analysis. The rate of major bleeding was not significantly different between groups (relative risk [RR]: 1.57, 95% CI: 0.93-2.65, P=0.09, I2=34%). However, the rate of clinically relevant non-major bleeding (CRNMB) was significantly higher in the DOACs group (RR: 1.98, 95% CI: 1.34-2.91, P=0.0005, I2=0%). The risk of recurrent VTE was not significantly different between groups (RR: 0.72, 95% CI: 0.41-1.28, P=0.27, I2=0%).ConclusionsThe current data suggests that treatment of GI cancer-associated thrombosis with DOACs significantly increases the risk of CRNMB, and a trend towards major bleeding risk in DOACs group. The efficacy of DOACs for preventing recurrent VTE in GI cancer was comparable to that of LMWHs.Trial registration: INPLASY202180113