Thromboembolic events and thromboprophylaxis associated with immunomodulators in multiple myeloma patients: a real-life study

The aim of this study is to assess international guidelines implementation concerning thromboprophylaxis strategy in myeloma patients treated with immunomodulatory drugs. This retrospective study includes multiple myeloma patients treated with immunomodulatory drugs between 2014 and 2017 in the Hematology department of a teaching hospital (Hospices Civils de Lyon, France) and followed by the multidisciplinary care plan for cancer outpatients ONCORAL (ONCological care for outpatients with ORAL anticancer drugs). Data from immunomodulatory drugs administration, thromboprophylaxis strategy and thrombotic events were collected from medical files. Adherence to 2010 International Myeloma Working Group (IMWG) guidelines was assessed. 213 patients received at least one immunomodulatory drug: lenalidomide (60.9%), pomalidomide (24.0%) and thalidomide (15.1%). About two third of treatment lines (66.2%) were in accordance with IMWG recommendations. Among the others, 30.5% and 69.5% had thromboprophylaxis, respectively, superior or inferior to IMWG recommendations. 37 venous thrombotic events and 4 arterial thromboembolisms (one patient experienced both a stroke and deep venous thrombosis simultaneously) were reported. Thromboprophylaxis was systematically performed in myeloma patients treated with immunomodulatory drugs in this real-life retrospective cohort. However, the choice of anticoagulant or anti-platelet agent remains debatable, as adherence to existing guidelines was variable.