Due to the absence of M protein in serum and urine, our patient did not meet the criteria for the diagnosis of MM but was labeled as an NSMM after the second MRI scan revealed a new bone lesion at the level of the L1 vertebral body, several other enlarged lesions (between 5 and 10 mm) within the “salt and pepper” marrow infiltration and confirmed by a positive bone marrow biopsy for plasmacytosis. This evidence concerns the gene MYOM2 and Miyoshi myopathy.