TP53 and Miyoshi myopathy: Mutation frequencies were of 3.1% (4/129), 25% (6/24), and 20% (2/10) in MM, pPCL and sPCL patients, respectively (Freeman-Halton test, P = 0.0005), in line with the notion that TP53 mutations are associated with aggressive forms of plasma cell dyscrasias and have a role in tumor progression than initiation [6, 7].