American Society of Hirudotherapy

Treatment of cancer-associated thrombosis: The evolution of anticoagulant choice and clinical insights into practical management

Research article published in Critical reviews in oncology/hematology (2021)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Narrative reviewClinical TrialsRiess et al. · Critical reviews in oncology/hematology, 2021

Abstract

Low-molecular-weight heparin (LMWH) therapy is recommended over vitamin K antagonists (VKAs) for the treatment of cancer-associated thrombosis (CAT) and extended therapy is recommended in those with active cancer to prevent recurrent thrombosis. However, the inconvenience of daily subcutaneous injections and the cost of LMWH therapy hinder long-term use. Observational data demonstrate that persistence with LMWH therapy is low in clinical practice and that many patients are switched to oral alternatives - namely VKAs and direct oral anticoagulants (DOACs). Recently, the efficacy and safety of apixaban, edoxaban, and rivaroxaban versus LMWH therapy for the treatment of CAT have been demonstrated in randomized trials. This review provides a critical evaluation of studies with DOACs in this setting and an update on the guidance regarding anticoagulant use for the treatment of CAT. In recognition of the heterogeneity of patients with cancer and the challenges of CAT, patient cases with expert clinical perspectives are presented.

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

Publication typeJournal ArticleReview
Indexed MeSH termsAnticoagulantsHeparin, Low-Molecular-WeightHumansNeoplasmsThrombosisVenous Thromboembolism

Summary

Peer-reviewed clinical and outcomes research relevant to medicinal leech therapy and its biology. Indexed in PubMed and verified against the NCBI record.

Why This Matters for Hirudotherapy

This review examines the evolving landscape of anticoagulant choice for cancer-associated thrombosis (CAT), critically evaluating the efficacy and safety of direct oral anticoagulants—apixaban, edoxaban, and rivaroxaban—against low-molecular-weight heparin (LMWH) as demonstrated in randomized trials, alongside practical management challenges such as low patient persistence with LMWH injections in active cancer. For ASH and the hirudotherapy community, this work offers valuable context because anticoagulant selection, dosing, and bleeding-risk management are core concerns in leech therapy, where hirudin—the medicinal leech's potent direct thrombin inhibitor—sits within the same broader anticoagulant framework; understanding how different anticoagulant strategies are compared in complex, high-risk populations informs clinical decision-making around leech use and concurrent anticoagulation. An important caveat is that the review focuses specifically on oral anticoagulants and LMWH for CAT and does not address hirudin-based agents or leech therapy directly, so its findings are not directly transferable to hirudotherapy protocols.

Citation

Treatment of cancer-associated thrombosis: The evolution of anticoagulant choice and clinical insights into practical management.

Riess et al. · Critical reviews in oncology/hematology, 2021

Added to ASH library: May 29, 2026 · Site last updated: June 18, 2026

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