Cancer complicated by thrombosis and thrombocytopenia: still a therapeutic dilemma

Abstract

Individuals who have thrombocytopenia and cancer-associated thrombosis (CAT) are difficult to manage because they have a high risk of bleeding and recurrent thrombosis. The International Society on Thrombosis and Haemostasis guidelines for the management of thrombocytopenia in patients with CAT suggest two main approaches: either complete anticoagulation with transfusion support if necessary, or dose-modified anticoagulation while the platelet count is <50×109/L. Nevertheless, rather than being based on information from randomized controlled trials (RCTs), these recommendations were based on expert consensus. Recent research from two different countries has shown how this cohort’s management and results vary widely. While the United Kingdom study, Cancer-Associated Venous Thrombosis and Thrombocytopenia, found no significant differences in bleeding or recurrent thrombosis between full dose and modified dose groups, the North American Thrombocytopenia Related Outcomes with Venous thromboembolism study demonstrated a significantly lower risk of bleeding events in those receiving modified dose anticoagulation compared to full dose, without an increased risk of recurrent VTE. Therefore, an RCT is required to assess the best course of action for patients with CAT and thrombocytopenia. To define the standard of care for the management of patients with CAT and thrombocytopenia, a full-scale trial called the START randomized trial (STrategies for Anticoagulation in patients with thRombocytopenia and cancer-associated Thrombosis) is an international, multi-site pilot study that compares the use of platelet transfusions plus higher dose anticoagulation to modified dose anticoagulation in patients with thrombocytopenia and CAT receiving anticoagulation.