Frequency and Risk Factors for Venous Thromboembolism Among Patients with Multiple Myeloma or Aggressive Lymphoma: A 6-Year Single Center Retrospective Analysis

Background and Aims: Patients with hematologic malignancies are characterized by presence of altered hemostatic system, which translates into a high risk of venous thromboembolism (VTE) with an estimated annual incidence of VTE higher when compared with the general population (0.5% vs 0.1%). Moreover, VTE contributes to morbidity and mortality in these patients and is a frequent complication of anticancer therapy. Even VTE is clearly associated with decreased survival, the development of validated scores delineate the risk of VTE by hematological disorders subtype still lacking. In the current study, the frequency and the risk factors associated with VTE were examined among a cohort of patients with aggressive lymphoma and multiple myeloma.

Methods: We retrospective analyzed clinical data of 231 patients with multiple myeloma and 227 patients diagnosed with aggressive lymphoma, followed in our institute from January 2015-December 2020. Among patients affected by myeloma, extramedullary disease was observed in 18% of patients. Among the lymphoma cohort, the most common type was diffuse large B-cell lymphoma (84%), followed by mantle cell lymphoma (8%), peripheral T cell lymphoma (4%), Burkitt lymphoma (2%), and primary mediastinal large B-cell lymphoma (2%).

Results: Fourty-six (19.9%) patients with diagnosis of multiple myeloma experienced a VTE, in a median follow-up of 23.09 month (range, 1.01-135.95). Half of patients (50%) had TVP, followed by EP in 28% and TVS in 22% of patients. VTE occurred in older age (pV=0.027), bone disease (pV=0.002), and the presence of central venous catheter (pV<0.001). Instead, no clinical and laboratory features at diagnosis affect the occurrence of thrombosis in patients with myeloma. Interesting, Lenalidomide-based therapy, monoclonal antibody-based therapy, and Carfizomib-based therapy increase the risk of VTE (HR 2.55 (1.31-4.95), pV=0.005; HR 2.36 (1.07-5.19), pV=0.037; HR 6.1 (2.8-13.6), pV<0.001; respectively). Even in patients with aggressive lymphoma the frequency of VTE was 19.8% (n=45) in a median follow up of months 28.87 (range, 0.23-177.18), despite 55.5% underwent thromboprophylaxis treatment. Older patients (pV= 0.029), with concomitant HIV infection (pV=0.031), and with spleen involvement (pV=0.022) were risk factors of development of VTE. Moreover, higher level of LDH (pV=0.042), leukocytosis (pV=0.004) and higher neutrophil-to-lymphocyte ratio (NLR) (pV=0.022) were significantly associated with increased risk of thrombosis. In our analysis, VTE did not significantly affect the overall survival of patients with myeloma and aggressive lymphoma.

Conclusions: VTE is a frequent complication in patients with multiple myeloma or aggressive lymphoma, and about 20% of these patients presented VTE during therapy. In our cohort of multiple myeloma, the therapeutic approach seems play a crucial role in development of thrombosis, although clinical presentation had less impact on VTE. In patients affected by aggressive lymphoma, NLR, a new inflammatory status marker, turns out to be an independent risk factor for VTE. This study showed new clinical and therapeutic risk factors for VTE, but the development of a predictive model for identifying patients with myeloma and lymphoma at high risk for developing thrombosis is an unmet need in clinical management.

No relevant conflicts of interest to declare.