Bayer Pharma AG

Essence of this Article

Anticoagulant treatment in patients with cancer with venous thromboembolism (VTE) can be a challenge as treatment may often be interrupted by invasive procedures or thrombocytopenia caused by chemotherapy. Oral vitamin K antagonists (VKAs) may not always be appropriate in patients with cancer; low molecular weight heparins (LMWHs), in addition to unfractionated heparin (UFH) and fondaparinux, are, therefore, preferred for patients with cancer. The risk of recurrent VTE is higher in patients with cancer than in those without and can depend on a number of factors including: the presence of metastatic cancer; treatment with chemotherapy; and the type of cancer.

Treatment of deep vein thrombosis and pulmonary embolism in patients with cancer

Anticoagulant treatment in patients with cancer with VTE can be a challenge because it may often be necessary to interrupt treatment because of invasive procedures or thrombocytopenia caused by chemotherapy.

  • Oral VKAs may not always be appropriate in patients with cancer because of unpredictable levels of anticoagulation resulting from malnutrition, nausea, vomiting and diarrhoea. Therapeutic monitoring, as required with warfarin, may also be challenging in this situation299, 300
    • There can be undesirable interactions with VKAs in patients receiving chemotherapy
    • The need for invasive therapeutic interventions (e.g. drainage procedures) may require reversal of anticoagulation, for which VKAs would not be suitable, owing to their long half-life301
  • LMWHs, in addition to UFH and fondaparinux, are an alternative to VKAs for the treatment of VTE in patients with cancer284, 289, 290, 293, 302, 303
    • In the CLOT study of acute VTE treatment, the LMWH dalteparin demonstrated superior efficacy compared with VKAs for the incidence of recurrent VTE with no significant difference in the incidence of major bleeding;299 however, the ACCP came to the overall conclusion that, taking into account the evaluation of further studies in which LMWH and VKAs have been compared, efficacy would in fact be similar between LMWH and VKA. The reasons for favouring LMWH relate to the difficulties in using oral VKAs in some patients with cancer (because of nausea, vomiting, drug interactions, etc) rather than a true difference in efficacy301

Click here for a summary of deep vein thrombosis (DVT) and pulmonary embolism (PE) treatment guidelines

Risk factors for recurrence

The risk of recurrent VTE is higher in patients with cancer than in those without cancer.304 A limited amount of data exists regarding the risk of recurrent VTE in patients with cancer; however, the annual risk is estimated at 15%.305 As a result of the high mortality rate in patients with VTE and cancer, estimating the long-term risk of recurrence is challenging.306

The risk of recurrence can depend on a number of factors:

  • The presence of metastatic cancer
  • Treatment with chemotherapy
  • How rapidly the cancer is progressing
  • The presence of active cancer
    • This is one of the most important factors that influences the risk of recurrent VTE after stopping VKA therapy285, 307
  • Type of cancer
    • Adenocarcinoma, lung or gastrointestinal malignancies have been shown to be associated with the highest risk of recurrence285
  • Age and time from cancer diagnosis
    • Patients who were <65 years of age or who presented with VTE <3 months from cancer diagnosis were shown to be at increased risk of recurrent DVT or PE, as shown by registry data308

Anticoagulation for the treatment of VTE is usually administered for at least 3–6 months in patients with cancer, and treatment may be extended indefinitely until cancer has resolved.309


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