How will patients with smoldering multiple myeloma be impacted by the new diagnostic criteria?
Welcome to Managing Myeloma. My name is Dr. Jatin Shah. I am associate professor of medicine at the Department of Lymphoma and Myeloma at MD Anderson Cancer Center, director of myeloma clinical and translational research, and program director of the lymphoma and myeloma fellowship. I am frequently asked, “How will patients with smoldering multiple myeloma be impacted by the new diagnostic criteria?” That is a very important question that impacts clinical care and patients. First, I would like to review with you what the new International Myeloma Working Group (IMWG) criteria are for the diagnosis of symptomatic myeloma. Historically, we used the CRAB criteria to identify patients with symptomatic myeloma requiring therapy, and those would include patients with elevated calcium, renal dysfunction with a creatinine greater than 2, anemia with hemoglobin less than 10, or lytic lesions identified on the skeletal survey. The new IMWG criteria for diagnosis of symptomatic myeloma included additional myeloma-defining events, and this includes clonal plasma cells in the bone marrow greater than 60%, serum-free light chain ratio equal or greater than 100, or more than one MRI focal lesion (≥5 mm). It is important, therefore, then to look at those three additional myeloma-defining events in addition to the CRAB criteria. Those three events, including clonal plasma cells greater than 60%, identified a subset of patients who are at risk for progression of multiple myeloma or symptomatic myeloma of 50% within the next 2 to 3 years. Similarly, the other risk factors also identify patients with high risk of developing symptomatic myeloma in the next 18 to 24 months. So, for patients with smoldering myeloma, it is important to identify these patients who we define as ultra high‑risk myeloma previously with these three additional criteria to be transitioned over to consideration for therapy. The rest of the smoldering myeloma patients with low risk, intermediate risk, or high risk still do not warrant therapy, and so, when we ask the question, “How will patients with smoldering myeloma be impacted by the new diagnostic criteria?” ultimately these new multiple myeloma-defining events affect a minority of patients who would be transitioned over to receiving therapy. The vast majority of patients with smoldering myeloma greater than 90% still will have smoldering myeloma and do not need therapy. Despite some of the recent data with trials demonstrating activities of smoldering myeloma, the current standard care for smoldering myeloma patients is not to receive systemic therapy at this point in time and continue the watchful waiting as only those patients with the ultra-high risk of the new myeloma-defining events as described would be transitioned and have an impact in their therapy with earlier therapy.
I hope this is helpful in answering the question of how patients with smoldering myeloma are impacted by the new diagnostic criteria. I thank you for viewing this activity, and for additional resources, please view the other educational activities on ManagingMyeloma.com.
Please view the Updated Criteria for the Diagnosis of Multiple Myeloma.
Reviewed on January 17, 2017 for clinical relevance.