Usual risk factors do not predict venous thromboembolism in newly diagnosed myeloma treated with immunomodulatory drugs

Prediction of venous thromboembolism in patients with multiple myeloma treated with lenalidomide, bortezomib, dexamethasone, and transplantation: Lessons from the substudy of IFM/DFCI 2009 cohort

BACKGROUND

Venous thromboembolism (VTE) is a concern for patients with newly diagnosed multiple myeloma.

OBJECTIVES

We aimed to evaluate VTE incidence, risk factors, and risk score.

PATIENTS/METHODS

We performed a substudy of the "Intergroupe Francophone du Myelome 2009" randomized controlled trial.

RESULTS

We assessed 700 patients receiving lenalidomide/bortezomib/dexamethasone, followed or not by autologous hematopoietic stem cell transplantation. VTE incidence at 6 months was 4.8% (95% confidence interval [CI]: 3.3-6.9%) and 1.5% (95% CI: 0.8-2.9%) from 6 to 12 months. Using multivariate analysis we confirmed history of VTE (odds ratio 5.1 [1.6-16.7], P = .007) as a strong VTE-related risk factor, invalidated erythropoietin exposure (0.6 [0.2-1.7], P = .3) as risk factor, and added two new risk factors: fracture at diagnosis (2.6 [1.3-5.5], P = .01), and serum gamma globulin level > 27 g/L (2.8 [1.2-6.8,] P = .02). Moreover, we noticed that VTE occurred earlier in patients with gamma globulin levels >27 g/L, suggesting a need to revisit the thromboprophylaxis timeframe. Heparin administration was associated with a decreased risk (0.3 [0.1-0.7], P = .005) but failed to erase the risk regardless of dose. The area under the receiver operating characteristic curve of the IMPEDE VTE score was 0.67, as previously reported, confirming our cohort was well representative.

CONCLUSIONS

Prospective studies are warranted in light of these results to improve VTE risk stratification and to design adapted thromboprophylaxis in terms of timing and dose.

Thrombin generation in newly diagnosed multiple myeloma during the first three cycles of treatment: An observational cohort study

BACKGROUND

Multiple myeloma (MM) is associated with a high risk of thrombosis, particularly during the first months of treatment including immunomodulatory drugs (IMiDs). There is no consensus on prevention of thromboembolic risk in patients with de novo MM, and identification of patients requiring anticoagulant thromboprophylaxis remains challenging. Evaluating coagulability by an in vitro thrombin generation (TG) test might be a way of identifying such patients.

OBJECTIVE

To determine whether TG assessment could reveal an increase in coagulability during the first three chemotherapy cycles.

METHODS

This prospective and longitudinal observational study included patients newly diagnosed with MM. TG was determined in platelet-rich and platelet-poor plasma using calibrated automated thrombography with a low tissue factor (TF) concentration.

RESULTS

Seventy-one patients were enrolled, allowing TG analysis during 213 chemotherapy cycles. TG remained unchanged throughout follow-up irrespective of treatment regimen, but values determined before cycles 2 and 3 were significantly higher in patients receiving iMiDs-containing regimens. No association was found between TG and its changes and thrombosis occurrence during follow-up: venous thrombosis in eight patients; no cardiovascular event. A significantly (87%) lower risk of venous thrombosis was observed in patients receiving prophylaxis with a low-molecular-weight heparin (LMWH; OR: 0.13 (95% CI: 0.02-0.76). Neither bortezomib- nor dexamethasone-containing regimens were associated with thrombotic risk. Changes in TG, as studied, were not associated with thrombotic events.

CONCLUSIONS

The only factor associated with a reduction in early thrombotic risk was prophylaxis with LMWH. The issue of how to identify patients requiring prophylactic anticoagulation remains unresolved.