CXCR4 and mantle cell lymphoma: The aim of the present, prospective PET/MRI study was, therefore, to investigate whether whole-body CXCR4 imaging of MCL using [68Ga]Pentixafor-PET is feasible for the assessment of disease burden in this lymphoma subtype, and also to compare it to the clinical standard, [18F]FDG-PET.