Not all MGUS needs a bone marrow biopsy
A bone marrow biopsy and skeletal survey via whole-body CT or conventional radiographs can be deferred in patients with low-risk MGUS and no bony symptoms. Using the Mayo Clinic risk stratification model, low risk is defined as a serum M protein of 1.5 g/dL or less on SPE, an IgG isotype, and a normal free light-chain ratio.
The lifetime risk of progression in patients with MGUS who meet all three criteria is only about 2%. They can be followed at 6 months with an SPE, free light-chain testing, a CBC, and serum calcium and creatinine, then annually thereafter.
“For those who aren’t in this low-risk category, we actually do need to do a bone marrow test,” according to Dr. Mikhael. “Then, based on that, if they have malignancy, send them to a myeloma geek like me or to another hematologist. And if they don’t have a malignancy, they can be followed at 6 months and then subsequently at least every year.”
Dr. Mikhael has received research grants from AbbVie, Celgene, and Sanofi.