A retrospective cohort study of venous thromboembolism(VTE) in 1035 Japanese myeloma patients treated with thalidomide; lower incidence without statistically significant association between specific risk factors and development of VTE and effects of thromboprophylaxis with aspirin and warfarin

Platelet Parameters as Biomarkers for Thrombosis Risk in Cancer: A Systematic Review and Meta-analysis

Cancer-associated thrombosis (CAT) is a major cause of both morbidity and mortality in cancer patients. Platelet count has been investigated as a predictor of CAT in various settings while knowledge on platelet activation parameters is sparse. This report provides a systematic review and meta-analysis on available literature on associations between platelet count and/or function and arterial and venous thrombosis in adult cancer patients. The review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. PubMed and Embase were searched up to March 2022. The National Heart, Lung, and Blood Institute's tools were used for quality assessment. In total, 100 studies were included which investigated the association between CAT and platelet count (n = 90), platelet indices (n = 19), and platelet function/activation markers (n = 13) in patients with solid cancers (n = 61), hematological cancers (n = 17), or mixed cancer types (n = 22). Eighty-one studies had venous thrombosis as their outcome measure, while 4 had arterial thrombosis and 15 studies had both. We found significantly elevated odds ratio of 1.50 (95% confidence interval: 1.19-1.88) for thrombosis with higher platelet counts. We saw a tendency toward an association between markers of platelet activation in forms of mean platelet volume and soluble P selectin and both arterial and venous thrombosis. Only one study investigated dynamic platelet function using flow cytometry. In conclusion, platelet count is associated with CAT across different cancer types and settings. Platelet function or activation marker analysis may be valuable in assisting thrombosis risk assessment in cancer patients but is sparsely investigated so far.

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.

Risk of thromboembolic events associated with different multiple myeloma regimens in Taiwan: a nested case-control study

Although novel agents for multiple myeloma (MM) have a better response rate and survival in both newly diagnosed and relapsed/refractory MM patients, concerns regarding the association between MM treatments and thromboembolic events have been raised. The aim of this population-based study was to examine the association between different combinations of MM treatments and the risk of thromboembolic events. We conducted a nested case-control study using the Taiwan Cancer Registry (TCR) and National Health Insurance Research Database (NHIRD). Adult patients newly diagnosed with MM and treated with at least one of the immunomodulatory agents between 2008 and 2016 were identified. Among them, we further identified patients who developed thromboembolic events as cases and selected controls matched by age, sex and duration of MM diagnosis at a ratio of 1:5. The index date was defined as the day one year before the diagnosis date of thromboembolic events in the case group and the corresponding date in the control group. Conditional logistic regression was used to examine the association between different MM treatment regimens and the risk of thromboembolic events. A total of 4,180 newly diagnosed MM patients treated with at least one of the immunomodulatory agents were identified (mean age: 67.2 years; male: 55.7%). In this MM cohort, we further identified 388 cases and 1,940 matched controls (mean age: 71 years; male: 64.2%). The use of a thalidomide/bortezomib/steroid combination (odds ratio (OR) 2.95 [95% confidence interval (CI) 1.47-5.95]), thalidomide monotherapy (OR 3.33; 95% CI, 1.59-6.94), and a thalidomide/steroid combination (OR 4.24; 95% CI, 2.00-8.98) were associated with an increased risk of thromboembolic events. Other risk factors, particularly a history of thromboembolic events, including ischemic heart disease and pulmonary embolism, were significantly associated with increased risk of thromboembolic events. We found that the use of thalidomide alone and in specific combinations was associated with an increased risk of thromboembolic events.

Thrombosis events in Chinese patients with newly diagnosed multiple myeloma

A high risk of thrombosis is seen in patients with newly diagnosed multiple myeloma (NDMM), particularly those treated with immunomodulatory drugs (IMiDs). Large cohorts addressing the thrombosis issue of NDMM patients in Asia are lacking. We retrospectively analyzed the clinical information of NDMM patients diagnosed in Zhongshan Hospital Fudan University, a national medical center, from January 2013 to June 2021. Death and thrombotic events (TEs) were the endpoints. To investigate risk factors for TEs, the Fine and Gray competing risk regression models were created, in which unrelated deaths were labeled as competing risk events. A total of 931 NDMM patients were recruited in our study. The median follow-up was 23 months [interquartile range (IQR): 9-43 months]. Forty-two patients (4.51%) developed TEs, including 40 cases (4.30%) of venous thrombosis and 2 cases (0.21%) of arterial thrombosis. The median time from taking first-line treatment to TEs occurrence was 2.03 months (IQR: 0.52-5.70 months). The cumulative incidence of TEs was higher in patients treated with IMiDs than in those without IMiDs (8.25 vs. 4.32%, p = 0.038). There was no difference in the incidence of TEs between lenalidomide-based and thalidomide-based groups (7.80 vs. 8.84%, p = 0.886). Besides, TEs occurrence did not adversely affect OS (p = 0.150) or PFS (p = 0.210) in MM patients. Chinese NDMM patients have a lower incidence of thrombosis than those in western countries. The risk of thrombosis was particularly increased in patients treated with IMiDs. TEs were not associated with inferior progression-free survival or overall survival.

Development and validation of a new risk assessment model for immunomodulatory drug-associated venous thrombosis among Chinese patients with multiple myeloma

BACKGROUND

Individuals with multiple myeloma (MM) receiving immunomodulatory drugs (IMiDs) are at risk of developing venous thromboembolism (VTE), a serious complication. There is no established clinical model for predicting VTE in the Chinese population. We develop a new risk assessment model (RAM) for IMiD-associated VTE in Chinese MM patients.

METHODS

We retrospectively selected 1334 consecutive MM patients receiving IMiDs from 16 medical centers in China and classified them randomly into the derivation and validation cohorts. A multivariate Cox regression model was used for analysis.

RESULTS

The overall incidence of IMiD-related VTE in Chinese MM patients was 6.1%. Independent predictive factors of VTE (diabetes, ECOG performance status, erythropoietin-stimulating agent use, dexamethasone use, and VTE history or family history of thrombosis) were identified and merged to develop the RAM. The model identified approximately 30% of the patients in each cohort at high risk for VTE. The hazard ratios (HRs) were 6.08 (P < 0.001) and 6.23 (P < 0.001) for the high-risk subcohort and the low-risk subcohort, respectively, within both the derivation and validation cohorts. The RAM achieved satisfactory discrimination with a C statistic of 0.64. The stratification approach of the IMWG guidelines yielded respective HRs of 1.77 (P = 0.053) and 1.81 (P = 0.063). The stratification approach of the SAVED score resulted in HRs of 3.23 (P = 0.248) and 1.65 (P = 0.622), respectively. The IMWG guideline and the SAVED score-based method yielded C statistics of 0.58 and 0.51, respectively.

CONCLUSIONS

The new RAM outperformed the IMWG guidelines and the SAVED score and could potentially guide the VTE prophylaxis strategy for Chinese MM patients.

Low incidence of thromboembolism in multiple myeloma patients receiving immunomodulatory drugs; a retrospective single-institution analysis

Anti-platelet agents or anticoagulants are administered for patients with multiple myeloma (MM) receiving immunomodulatory drugs (IMiDs) to prevent thrombotic events (TEs). However, there is a discrepancy between current guidelines and clinical practice in thromboprophylaxis and the varied incidence of TEs depending on patient cohort. Therefore, a consensus on the optimal thromboprophylactic strategy is needed. To determine an appropriate strategy for the prevention of TEs in MM patients receiving IMiDs, we performed a retrospective single-institution analysis. In total, 95 MM patients (62% male, median age 65 years, range 30-85 years) from November 2008 to January 2018 were recruited, and 140 cases were analyzed in the medical-record-based study. Thromboprophylactic drugs were given to 69% of patients, anti-platelet agents to 66%, and anticoagulants to 3.0%. Seven TEs (5.0%) and six bleeding events (4.3%) were observed, but no patients died from thrombohemorrhage. The median follow-up period was 184 days (range 21-2224), and the cumulative TE incidence was 1.7% at 3 months, 7.0% at 1 year, and 12.5% at 3 years. Multivariate analysis determined that age > 70 years (p = 0.012) and BMI < 18.5 kg/m² (p = 0.042) were the significant risk factors of TE. A low incidence of TEs was observed despite the low adherence to guideline recommendations for anticoagulant administration. These results suggest that anti-platelet agents are sufficient for thromboprophylaxis. A high-risk group of TEs in MM patients receiving IMiDs was identified, and a larger study is needed to confirm these findings.

Pomalidomide and dexamethasone combination with additional cyclophosphamide in relapsed/refractory multiple myeloma (AMN001)-a trial by the Asian Myeloma Network

Pomalidomide is a third generation immunomodulatory drug which in combination with dexamethasone, has been shown to be active in relapsed/refractory multiple myeloma. However, the data in Asian patients remain limited. We conducted a prospective phase two clinical trial in major cancer centers in Singapore, South Korea, Taiwan, Japan and Hong Kong to assess the efficacy and safety of pomalidomide and dexamethasone combination (PomDex) +/− cyclophosphamide in Asian patients with relapsed/refractory multiple myeloma who failed lenalidomide and bortezomib. Patients were treated with pomalidomide (4 mg daily for 21 days every 4 weeks) and dexamethasone (40 mg weekly). If there is less than a minimal response after three cycles of PomDex, cyclophosphamide 300 mg/m² can be added (PomCyDex). A total of 136 patients were enrolled. The median PFS was 9 and 10.8 months for the PomDex and PomCyDex group, respectively. The median OS was 16.3 months. This regimen appears to be active across age groups and prior lines of treatment. This combination was overall well tolerated with grade 3 and 4 adverse events of mainly cytopenias. PomDex is highly active and well-tolerated in Asian patients. The addition of cyclophosphamide can improve the response and outcomes further in patients with suboptimal response to PomDex.

A multicenter phase 2 study of pomalidomide plus dexamethasone in patients with relapsed and refractory multiple myeloma: the Japanese MM-011 trial

Background

The immunomodulatory agent pomalidomide in combination with low-dose dexamethasone has demonstrated efficacy and safety for the treatment of relapsed and refractory multiple myeloma (RRMM) in phase 2 and 3 trials. However, these trials enrolled very few Asian patients.

Methods

This phase 2 study investigated pomalidomide plus low-dose dexamethasone in 36 Japanese patients with RRMM after ≥2 prior therapies.

Results

Patients enrolled in the study had a relatively high disease burden (81 % Durie–Salmon stage II or III) and were heavily pretreated (median, 6.5 prior antimyeloma regimens). The overall response rate was 42 % (1 patient with complete response and 14 with partial response), with an additional 44 % (16 patients) achieving stable disease (SD). Response rates in patients aged ≤65 years and >65 years were 47 and 35 %, respectively. None of the five patients with extramedullary disease achieved a response, with three of them maintaining SD of short duration. Median progression-free survival was 10.1 months after a 7.7-month median follow-up, and the median overall survival was not reached. The most frequent grade ≥3 adverse events (AEs) were neutropenia (64 %), anemia (42 %), and thrombocytopenia (31 %). The most frequent nonhematologic grade ≥3 AEs were pneumonia and decreased appetite (8 % each). Adverse events in patients aged >65 years were similar to those in patients aged ≤65 years, except for a higher rate of grade ≥3 pneumonia.

Conclusions

Collectively, the results of this study demonstrate that pomalidomide plus low-dose dexamethasone is an effective and safe treatment for Japanese patients with RRMM, although careful attention needs to be paid to serious infections.

Trial registration: Clinicaltrials.gov NCT02011113