CXCR4 and Miyoshi myopathy: In order to determine the suitability of the high-affinity human CXCR4-specific probe Pentixafor as an in vivo MM PET tracer, NOD SCID mice were xenografted with MM.1S and OPM-2 cells and underwent consecutive [18F]FDG and [68Ga]Pentixafor PET.