Concomitant T2DM (p = 0.029) and increased B2M level at diagnosis (p = 0.012) were associated with a shorter time to the detection of solid SPM, whereas a lower PLT count at an MM diagnosis (<150,000) (p = 0.021) and a higher number of comorbidities (p = 0.003) predicted a shorter time to hemato-SPMs. This evidence concerns the gene B2M and Miyoshi myopathy.