Thromboembolism Incidence and Risk Factors in Multiple Myeloma After First Exposure to Immunomodulatory Drug-Based Regimens

Incidence of thromboembolism and associated factors in multiple myeloma patients treated with immunomodulatory drugs: a retrospective analysis in Belo Horizonte, Brazil

PURPOSE

The use of immunomodulators in the treatment of multiple myeloma (MM) patients has been associated with venous thromboembolism (VTE). Due to the increase in mortality of cancer patients, venous thromboembolism is an important concern for newly diagnosed multiple myeloma (NDMM) patients. The aim of this study was to determine the incidence of thromboembolic events and evaluate associated risk factors among Brazilian NDMM patients using immunomodulators.

METHODS

Real-life retrospective cohort study in two Brazilian institutions with newly diagnosed multiple myeloma (NDMM) patients treated with immunomodulators from January 2009 to December 2019. Data was collected from patients' medical records for the period of 1 year, and Cox regression was performed to identify risk factors on the development of VTE.

RESULTS

We included 131 patients of which there was a mean age of 61.5 years (SD 11.3), 51.9% female, and predominantly using thalidomide (97.7%) as immunomodulator. We found 9 VTE episodes among our patients, with a 12-month cumulative incidence of 6.97% (95% CI 3.41-12.24). Associated factors after multivariate analysis were recent sepsis, recent traumatic injury, previous VTE, and thromboprophylaxis.

CONCLUSION

Our real-life retrospective cohort presented a low incidence of VTE among Brazilian NDMM patients treated with immunomodulators.

Thrombosis in multiple myeloma: Risk estimation by induction regimen and association with overall survival

Lenalidomide-containing (R) triplet and quadruplet regimens are the standard of care for multiple myeloma (MM) and have been shown to increase the risk of thrombosis. The association between thromboembolism (TE) and survival in the novel multidrug era is not yet delineated. In this study, we evaluated the incidence of TE during the first year of MM diagnosis, its association with the type of induction regimen, and its impact on overall survival. We studied 672 newly diagnosed MM (NDMM) patients who received a triplet or quadruplet lenalidomide-based induction at the Mayo Clinic, Rochester. TE was diagnosed in 83 patients (12.4%). Of these, 56 (8.3%) had a deep venous thrombosis (DVT), 23 (3.4%) had a pulmonary embolism (PE) with or without the DVT, and 4 (0.6%) patients had a stroke. Carfilzomib-Rd (KRd) had the highest risk of TE (21.1%, 18/85), followed by quadruplets (11.1%, 5/45), bortezomib-Rd (9.6%, 51/531), and 0/11 (0%), treated with other lenalidomide-containing regimens. The difference in TE risk between KRd and the other regimens was statistically significant (OR = 2.6, p < .01). Nine patients developed a TE before being exposed to any treatment. Survival was significantly lower among patients that developed a TE (66 vs. 133 months, p < .01). The association of TE with reduced survival demonstrated in univariate analysis (HR = 2.2, 95% CI = 1.6-3.3) was maintained in the multivariable analysis adjusted for high-risk interphase fluorescence in situ hybridization (FISH), sex, age, receipt of an upfront transplant, the response at induction, and the International Staging System (ISS) (HR = 2.61, CI = 1.74-3.9). We conclude that TE is an important aspect of MM management, and effective management is especially relevant in the novel treatment era.

Abnormal metaphase cytogenetics predicts venous thromboembolism in myeloma: derivation and validation of the PRISM score

Although venous thromboembolism (VTE) is an important treatment and disease-related complication in myeloma, a validated risk prediction model including disease-specific variables such as cytogenetics or tumor burden is lacking. The aim of this study was to develop a new risk prediction model for VTE in the context of modern antimyeloma therapy. All consecutive patients diagnosed at the Cleveland Clinic between 2008 and 2018 and with available data on baseline candidate risk factors constituted the derivation cohort. The primary outcome was VTE (deep venous thrombosis/pulmonary embolism) within 1 year of treatment initiation. A multivariable model was used, and weights were derived from subdistribution hazard ratios to construct a risk score. The model was validated both by internal bootstrap validation and in an external validation cohort. The derivation cohort consisted of 783 patients. A 5-component risk prediction tool, named the PRISM score, was developed, including the following variables: prior VTE, prior surgery, immunomodulatory drug use, abnormal metaphase cytogenetics, and Black race. The c-statistic of the model was 0.622 (95% confidence interval [CI], 0.567-0.674). The model stratified patients into low, intermediate, and high risk, with 12-month cumulative VTE incidence of 2.7%, 10.8%, and 36.5%, respectively. Risk of VTE increased significantly with increasing score in both the derivation and the external validation data sets, with a subdistribution hazard ratio per 1-point increase of 1.28 (95% CI, 1.19-1.39; P < .001) and 1.23 (95% CI, 1.07-1.41; P = .004) respectively. Although the PRISM score can guide clinicians in identifying patients at a high risk of VTE, additional external validation is necessary for incorporation into routine clinical practice.