Use of direct oral anticoagulants in hematologic malignancies

Thrombosis is a common and serious event in cancer patients. While risk factors are well established in solid tumors and have lead to guidance regarding prophylaxis, similar data and recommendations are lacking for patients with hematologic malignancies. Likewise treatment for established venous thrombosis in cancer patients has shifted from low molecular weight heparin to direct oral anticoagulants (DOACs) based on favorable outcomes with the latter drugs in most tumor types while hematologic malignancies remain understudied and the appropriateness of DOAC use in these patients is less certain. Reasons for the knowledge gaps that have developed regarding management of thrombosis in hematologic malignancies include their relative rarity compared to solid organ cancer making large scale trials difficult to complete, and the particular nature of blood cancers and their treatment giving rise frequently to severe thrombocytopenia which is typically regarded as an exclusion from clinical trials.