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 narrative review traces the evolution of anticoagulant choice for cancer-associated thrombosis, noting that while LMWH has been recommended over vitamin K antagonists, its daily subcutaneous injections, cost, and low real-world persistence drive switching to oral options, and that randomized trials have since shown apixaban, edoxaban, and rivaroxaban to be efficacious and safe versus LMWH in this setting. It is relevant to hirudotherapy as part of the broader anticoagulation landscape that frames why interest persists in alternative and locally acting antithrombotic strategies, including the leech-secretome molecules historically studied as anticoagulants. As a review summarizing others' work and presenting illustrative expert cases, it generates no new trial data, does not address hirudotherapy, and reflects guidance current to its 2021 publication.

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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