Venous and arterial thrombotic risks with thalidomide: evidence and practical guidance.

Oral immunomodulatory drugs (IMiDs), namely thalidomide, lenalidomide and pomalidomide, interfere with several pathways important for disease progression. Today they play a crucial role in the treatment of multiple myeloma patients, and have considerably improved myeloma outcomes. These agents, and thalidomide in particular, are associated with higher rates of thromboembolic events, both venous and arterial. Individual risk factors for thromboembolic events include advanced age, previous history of thromboembolism, an indwelling central venous catheter, comorbid conditions (e.g. infections, diabetes, cardiac disease, obesity), current or recent immobilization, recent surgery and inherited thrombophilic abnormalities. Cancer therapy and cancer itself also increase the risk of thromboembolic events. The aim of this review is to help clinicians to define the risk of thrombotic events in patients treated with thalidomide and thus to provide practical recommendations to manage thromboprophylaxis in these patients.