Smoldering Multiple Myeloma: Defining the Threshold for Treatment
Posted: Monday, January 18, 2021
The debate surrounding the definition of “smoldering myeloma” rages on, only adding to the challenges associated with differentiating those at low risk, high risk, or “ultra-high risk” for developing multiple myeloma, according to Natalie S. Callander, MD, of the University of Wisconsin Carbone Cancer Center Myeloma Program. Stratifying these patients is crucial to avoid under- or overtreatment. Dr. Callander discussed the importance of risk stratification in these patients and current treatment strategies in her presentation at the 2020 NCCN Annual Congress on Hematologic Malignancies, highlights of which were published in JNCCN–Journal of the National Comprehensive Cancer Network.
Although the debate continues as to whether patients with smoldering myeloma should receive modest treatment to slow disease progression or aggressive treatment to completely stop multiple myeloma from developing, the consensus is that patients defined as having low-risk smoldering myeloma may forgo treatment in favor of observation, but follow-up is necessary. Meanwhile, high-risk patients should be enrolled in clinical trials, but in the absence of a trial option for these individuals, lenalidomide-based therapy with or without dexamethasone is recommended.
The SLiM CRAB criteria (referring to the percentage of clonal plasma cells, free light chain ratio, and marrow deposits) help to identify patients who should be treated for myeloma. In addition, an advanced imaging modality—whole-body MRI, pelvic/spine MRI, low-dose whole-body CT, or PET/CT—is necessary to discriminate smoldering myeloma from myeloma. However, other models are frequently used to risk-stratify patients for disease progression, and Dr. Callander urged caution when choosing any one method. “There is not a perfect overlap, so before you hang your hat on any one of these methods, you probably still need to use a bit of caution until we understand more,” she commented.
Disclosure: Dr. Callander reported no conflicts of interest.
