P. Verhamme MD, PhD

The role of direct oral anticoagulants in the management of cancer-associated thrombosis

Cancer patients are at an increased risk of venous thromboembolism (VTE). The current standard initial treatment of an acute episode of VTE in cancer patients consists of the administration of three to six months of subcutaneous low molecular weight heparin (LMWH) at a dose adjusted to the body weight. The efficacy and safety profile of LMWHs are well established, but a drawback of these agents is that they require daily subcutaneous administration. In addition, they are mainly cleared through the kidneys, and their use in patients with severe renal insufficiency may require dose reduction or monitoring of the anti-Xa activity. To address the issues with LMWH, several direct oral anticoagulants (DOAC) have been developed for the treatment of VTE. In contrast to LMWHs and vitamin K antagonist, DOACs directly interfere with thrombin or activated factor X (FXa). DOACs have now become standard treatment options in the general management of VTE, but until recently, there were no results of clinical trials specifically assessing the role of DOACs in the treatment of cancer-associated thrombosis. Recently, the Hokusai VTE cancer study and preliminary data from the Select-D trial demonstrated that DOACs are non-inferior to LMWH in preventing recurrent VTE. However, both studies also show that this comes at the cost of an increased rate of both major and clinically-relevant non-major bleeding. Especially in the subgroup of patients with gastrointestinal cancer, the benefit in VTE recurrence with the DOAC seems to be outbalanced by a significantly increased bleeding risk. Based on the available results, DOACs might represent an interesting alternative for LMWH in certain subgroups of patients, but with an important list of exceptions. It seems reasonable not to use DOACs in patients with a high bleeding risk, and especially in patients with gastrointestinal cancer, DOACs should not be the first-line choice. In summary, while LMWHs are currently the standard of care in the acute management of cancer-associated thrombosis, the advent of DOACs is welcomed for patients at a low bleeding risk who are in need of long-term anticoagulation.

(BELG J HEMATOL 2019;10(4):169–76)

A-140 AN OPEN CONFORMATION OF ADAMTS13 IS A HALLMARK OF ACUTE ACQUIRED THROMBOTIC THROMBOCYTOPENIC PURPURA

A-140 STAPHYLOCOCCUS AUREUS AND STAPHYLOCOCCUS LUGDUNENSIS BIND VON WILLEBRAND FACTOR TO OVERCOME SHEAR STRESS AND CAUSE ENDOCARDITIS

A-132 PEAR1 PROMOTER METHYLATION IS ASSOCIATED WITH PLATELET AND WHITE BLOOD CELL PHENOTYPES IN THE MOLI-FAMILY COHORT

A-135 CLUMPING FACTOR A, VON WILLEBRAND FACTOR-BINDING PROTEIN AND VON WILLEBRAND FACTOR TO THE VESSEL WALL

A-112 ABSENCE OF PEAR1 DOES NOT AFFECT MURINE PLATELET FUNCTION

Guidance for the prevention and treatment of venous thromboembolism in cancer patients

Summary

Venous thrombosis is a common complication in cancer patients and thromboembolism is the second most common cause of death. Several practice guidelines provide recommendations for the management of cancer-associated thrombosis. However, these guidelines do not sufficiently cover commonly encountered clinical challenges. With this expert panel, consisting of medical oncologists, haematologists, internists and thrombosis specialists, we aimed to develop a practical Belgian guidance for adequate prevention and treatment of cancer-associated thrombosis that covered several challenging situations encountered in daily clinic. This paper discusses the following topics: type and treatment duration of anticoagulant therapy, recurrent VTE despite anticoagulation, anticoagulation in case of renal impairment, liver disease and thrombocytopenia, the role of anti-Xa monitoring, central venous catheter-associated thrombosis, the position of direct oral anticoagulants and thromboprophylaxis, both in ambulatory and hospitalised patients. For an overview of the recommendations formulated by the expert panel, we refer to the key messages for clinical practice in this article.

(BELG J HEMATOL 2016;7(6):217–23)