Abstract Number: PB0928
Meeting: ISTH 2022 Congress
Theme: Venous Thromboembolism » Cancer Associated Thrombosis
Background: Data is needed on direct oral anticoagulants (DOACs) for treatment of venous thromboembolism (VTE) in hematological malignancies (HM). Retrospective studies to date lacked a control group and included patients with atrial fibrillation and/or VTE, but not VTE alone.
Aims: Assess incidence of VTE recurrence and bleeding in HM patients treated with low molecular weight heparin (LMWH) or DOACs for acute VTE.
Methods: Retrospective cohort study including patients with active HM and newly-diagnosed VTE treated at Rabin or Meir Medical Centers (1/2015-7/2021). Patients indexed on the first day of anticoagulation for VTE and followed for 12 months. The primary outcome was a composite of recurrent VTE, clot progression, major bleeding or clinically relevant non-major bleeding (CRNMB). Cumulative incidence [95% confidence interval (CI)] was calculated for each anticoagulation group (LMWH, DOAC) and hazard ratios (HR) were calculated using cox-proportional hazards model, with death as a competing risk.
Results: 143 HM patients treated with LMWH (96) or DOACs (47) for acute VTE were included. Table 1 shows patient characteristics. HM was lymphoma in 83 (58%). DOAC-treated patients were older, had more pulmonary embolism and less splanchnic vein thrombosis.
The 12-month cumulative incidence of the primary outcome (Figure 1) was 24.2% (95% CI 15.9-33.5%; n=22) in the LMWH group and 18.5% (8.5-31.5%; n=8) in the DOAC group (HR 1.51 [0.695-3.297]). Two recurrent VTE occurred (both in the DOAC group while off-treatment). Nine (9.4%) LMWH-treated patients had major bleeding compared to 1 (2.1%) DOAC-treated patient (HR 4.85 [0.64-36.56]). There were 13 (13.5%) CRNMB cases in the LMWH group and 5 (10.6%) in the DOAC group (HR 1.44 [0.52-3.98]).
Conclusion(s): This study generates the hypothesis that DOACs may be a safe and effective alternative to LMWH for VTE in patients with lymphoma or plasma cell dyscrasia. Larger prospective studies are needed to confirm these findings.
Table
Patient characteristics, stratified for type of anticoagulation
Image
12-month cumulative incidence of recurrent VTE, major bleeding or CRNMB
To cite this abstract in AMA style:
Robinson R, Spectre G, Lishner M, Sharabi O, Robinson E, Hamburger Avnery O, Gafter-Gvili A, Raanani P, Leader A. Direct Oral Anticoagulants for Treatment of Venous Thromboembolism in Patients with Hematological Malignancies [abstract]. https://abstracts.isth.org/abstract/direct-oral-anticoagulants-for-treatment-of-venous-thromboembolism-in-patients-with-hematological-malignancies/. Accessed October 1, 2023.« Back to ISTH 2022 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/direct-oral-anticoagulants-for-treatment-of-venous-thromboembolism-in-patients-with-hematological-malignancies/