Peri-Transplant Venous Thromboembolism in Patients with Multiple Myeloma

Abstract

Introduction Risk of venous thromboembolism (VTE) is increased in patients (pts) with multiple myeloma (MM) as a result of the biology of the disease and the use of immunomodulatory drugs (IMiDs). These patients frequently undergo autologous hematopoietic cell transplantation (AHCT) transplantation in order to improve disease-free and potentially overall survival. We conducted this study to better understand the incidence and risk factors associated with peri-transplant VTE in this population. Methods 160 MM pts who received IMiD therapy and underwent AHCT between 6/2004 and 11/2016 at our institution were the subjects of this analysis. The peri-transplant period was defined as time from central venous catheter (CVC) insertion up to 60 days post-transplant. None of the pts received VTE prophylaxis during this period. Results All patients received at least one IMiD-based regimen before transplant including thalidomide (31%), lenalidomide (74%), pomalidomide (6%). Imids were stopped at a median of 38 days prior to collection (range 0 days-4 years). CVCs (double lumen n=103, triple lumen n=50, unknown n=7) were inserted a median of 2.5 days prior to mobilized blood collection (range 0-48 days) and were removed a median of 52.5 days after insertion (range 2-303 days). Twenty of 160 patients (12.5%) developed VTE in the peri-transplant period; there was 11 (55%) CVC-related VTE, 6 (30%) lower extremity VTE and 3 (15%) pulmonary embolism. There was no VTE-related death. Median platelet count at the time of VTE was 90 (range, 30-130) x109/L. Eleven VTEs occurred between time of initiation of progenitor cell mobilization and infusion (T-0), and 9 occurred between T-0 and 60 days post-transplant. The rate of catheter-related VTE that occurred before or after T-0 was similar (55%). Thirty-nine percent of pts had a catheter size of less than 14 french; 49% had a catheter size of 14 french or more; the size could not be collected in 12% of the pts. Rate of catheter-related VTE in pts with ≥ 14 and Conclusion In this retrospective single institution analysis, we found a 12.5% incidence of peri-transplant VTEs, which is higher than what was reported in patients receiving transplant for other malignancies [1]. The size of the catheter did not affect the risk of VTE. About half of the VTEs were catheter-related, half of which occurred before T-0. If confirmed on a larger scale, it may be beneficial to give VTE prophylaxis during mobilization to minimize this risk.