New research from the Hutchinson Institute for Cancer Outcomes Research (HICOR)- which is based at Fred Hutchinson Cancer Research Center- along with the University of Washington and the Seattle Cancer Care Alliance, identifies a simple way to help cancer doctors caring for patients with multiple myeloma to predict blood clots in order to take preventive action. The researchers established a set of risk factors that every doctor can use to determine which patients are most-likely to need blood thinners (anticoagulants) to prevent the dangerous side effect of blood clots associated with some of the newer treatments for this disease.
Venous thromboembolism (VTE)- blood clots in the veins- has been shown to be associated with treatment by an immunomodulatory drug (IMiD) in combination with a moderate-to-high dose of steroids. The results of this study, which were published in the July 2019 issue of JNCCN- Journal of the National Comprehensive Cancer Network, could have immediate implications for clinical practice and improve patient care.
"VTE is an under-recognized but frequently encountered complication to certain types of cancers and some treatment regimens," said Ang Li, MD, University of Washington. "VTE is common in patients with multiple myeloma receiving IMiDs, and can cause disability, delay or complicate chemotherapy, and in rare cases be fatal."
We're surprised that prophylactic anticoagulation, in any form, is under-utilized despite of its inclusion in the NCCN Guidelines for Cancer-Associated VTE for more than 10 years now. We think this study may help health care providers identify which newly-diagnosed multiple myeloma patients receiving IMiDs should receive preventive treatment with blood thinners."
Kristen M. Sanfilippo, MD, MPHS, study's senior author, Washington University and Siteman Cancer Center in St. Louis
The researchers used two different databases- featuring different populations- to derive and confirm risk factors for VTE in multiple myeloma patients. 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 IMiDs within 12 months of their multiple myeloma diagnosis. They determined five factors associated with likelihood of VTE: a prior history of VTE, surgery within 90 days, being 80 years of age or older, high steroid dose, and non-Asian race; and assigned different points to each of these factors. 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, versus 4% and 7% for those with a score of 1 or lower. The results were similar for the Veterans Health Administration group.
"With the increasing use of IMiDs for treating multiple myeloma, VTE risk is an ever-present and growing concern," said Bjorn Holmstrom, MD, Moffitt Cancer Center, Vice-Chair of the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) 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 had a word of caution about this new risk assessment model, despite the fact that it outperformed current recommendations. Until it can be prospectively validated, they only recommend that oncologists use it as a tool to supplement clinical decision-making.