Stratification Tool to Predict VTE in Patients With Multiple Myeloma Treated With Immunomodulatory Drugs
New research published by Li et al in JNCCN–Journal of the National Comprehensive Cancer Network has identified a way to help clinicians caring for patients with multiple myeloma to predict blood clots in order to take preventive action. The researchers established a set of risk factors to determine which patients are most likely to need anticoagulants to prevent venous thromboembolism (VTE) associated with treatment with an immunomodulatory drug in combination with a moderate-to-high dose of steroids.
“VTE is an underrecognized but frequently encountered complication [of] certain types of cancers and some treatment regimens,” said first study author Ang Li, MD, of the University of Washington. “VTE is common in patients with multiple myeloma receiving immunomodulatory drugs, and can cause disability, delay or complicate chemotherapy, and—in rare cases—be fatal.”
“We’re surprised that prophylactic anticoagulation in any form is underutilized, despite of its inclusion in the NCCN Guidelines® for Cancer-Associated VTE for more than 10 years now,” said senior study author Kristen M. Sanfilippo, MD, MPHS, of Washington University and Siteman Cancer Center in St. Louis. “We think this study may help health-care providers identify which newly diagnosed [patients with] multiple myeloma receiving immunomodulatory drugs should receive preventive treatment with blood thinners.”
Study Methods
The researchers used two different databases to derive and confirm risk factors for VTE in patients with multiple myeloma. They looked at data from 2,397 patients in the SEER-Medicare database and another 1,251 from the Veterans Health Administration, all of whom were prescribed immunomodulatory drugs within 12 months of their multiple myeloma diagnosis.
Researchers determined five factors associated with likelihood of VTE—a prior history of VTE, undergoing surgery within 90 days, being 80 years of age or older, dexamethasone dose, and non-Asian race. They assigned different points to each of these factors.
Findings
Within the SEER-Medicare group, patients with a score of 2 or higher experienced VTE at 3 and 6 months at a rate of 7% and 12%, respectively, vs 4% and 7% for those with a score of 1 or lower. The results were similar in the Veterans Health Administration group. The model stratified approximately 30% of patients in both cohorts as high-risk.
Hazard ratios were 1.85 (P < .01) and 1.98 (P < .01) for high- vs low-risk groups in the derivation and validation cohorts, respectively. In contrast, the method of stratification recommended in the current NCCN Guidelines for Cancer-Associated Venous Thromboembolic Disease demonstrated hazard ratios of 1.21 (P = .17) and 1.41 (P = .07) for the corresponding risk groups in the two data sets.
“With the increasing use of immunomodulatory drugs for treating multiple myeloma, VTE risk is an ever-present and growing concern,” said Bjorn Holmstrom, MD, of the Moffitt Cancer Center and Vice-Chair of the NCCN Clinical Practice Guidelines in Oncology Panel for Cancer-Associated Venous Thromboembolic Disease, who was not a member of the research team. “Providers need to vigilantly prescribe VTE prophylaxis to minimize risk of thrombosis. This study provided a simplified stratification tool to help guide providers to those patients with the highest risk of thrombosis. This type of risk assessment model will hopefully allow adherence and compliance to remain high.”
The researchers cautioned that until this new risk tool can be prospectively validated, they only recommend that oncologists use it to supplement clinical decision-making.
Disclosure: For full disclosures of the study authors, visit jnccn.org.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
