American Society of Hirudotherapy

Direct Oral Anticoagulants Versus Low-Molecular-Weight Heparin in Patients With Cancer-Associated Thrombosis: A Meta-Analysis of Randomized Controlled Trials.

Review published in The American journal of cardiology (2025)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Meta-analysisClinical TrialsDrug DevelopmentMousavi et al. · The American journal of cardiology, 2025

Abstract

Cancer-associated thrombosis (CAT) is a significant cause of morbidity and mortality in patients with cancer. Determining the optimal anticoagulant remains a clinical challenge. This meta-analysis aimed to compare the efficacy and safety of direct oral anticoagulants (DOACs) and low-molecular-weight heparin (LMWH) for CAT treatment. We systematically searched databases for randomized controlled trials (RCTs) comparing DOACs and LMWH in patients diagnosed with CAT. Efficacy outcomes were recurrent venous thromboembolism (VTE), deep vein thrombosis (DVT), and pulmonary embolism (PE). Safety outcomes comprised total bleeding, major bleeding, clinically relevant nonmajor bleeding (CRNMB), and all-cause mortality. We calculated incidence risk ratios (IRRs) with 95% confidence intervals (CIs) using a random-effects model. Subgroup analyses were conducted based on administered DOAC type. We identified 10 RCTs with 4713 participants (mean age 64.63 years, 50.58% male), including 2390 receiving DOACs and 2323 receiving LMWH. Compared to LMWH, the DOACs group demonstrated a statistically significant reduction in the incidence of VTE (IRR = 0.66, 95% CI 0.56 to 0.79). Total bleeding (IRR = 1.10, 95% CI 0.80;1.50) and mortality (IRR = 1.00, 95% CI, 0.89-1.12) did not differ significantly. Sensitivity analyses of studies with >100 participants and 6-month follow-up were consistent with overall results. In conclusion, DOACs were more effective than LMWH in reducing the risk of recurrent VTE and DVT in patients with CAT, with comparable safety profiles. The improved efficacy of DOACs positions them as a potentially advantageous therapeutic option for this patient population. Further research is warranted to optimize DOAC use in different cancer types and patient subgroups.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal ArticleMeta-AnalysisSystematic Review
Indexed MeSH termsHumansAdministration, OralAnticoagulantsHeparin, Low-Molecular-WeightNeoplasmsPulmonary EmbolismRandomized Controlled Trials as TopicThrombosisVenous ThromboembolismVenous Thrombosis

Summary

Cancer-associated thrombosis (CAT) is a significant cause of morbidity and mortality in patients with cancer. Determining the optimal anticoagulant remains a clinical challenge.

Why This Matters for Hirudotherapy

This meta-analysis of 10 randomized controlled trials (4,713 participants) compared direct oral anticoagulants with low-molecular-weight heparin for cancer-associated thrombosis, reporting reduced recurrent VTE with DOACs (IRR 0.66; 95% CI 0.56-0.79) and no significant differences in total bleeding (IRR 1.10; 95% CI 0.80-1.50) or mortality (IRR 1.00; 95% CI 0.89-1.12). The abstract is relevant to anticoagulant selection in cancer-associated thrombosis, a hematology/oncology issue, but it discusses pharmaceutical anticoagulants only and does not mention leeches, hirudin, or hirudotherapy. It provides no direct evidence about leech therapy or the leech secretome. Thus, any connection to hirudotherapy would be unsupported by this source.

Citation

Direct Oral Anticoagulants Versus Low-Molecular-Weight Heparin in Patients With Cancer-Associated Thrombosis: A Meta-Analysis of Randomized Controlled Trials.

Mousavi et al. · The American journal of cardiology, 2025

Added to ASH library: May 28, 2026 · Site last updated: June 18, 2026

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