The study, which was conducted at King's College London, involved 46 treatment-naive patients with suspected myeloma. Whole-body MRI and PET/CT agreed on a positive diagnosis in just 59% of patients. Information from whole-body MRI resulted in a decision to treat an additional 7% of patients, compared with PET/CT, but this was not a statistically significant result.

"Compared to [F-18 FDG PET/CT], [whole-body MRI] had a higher per-patient sensitivity for bone disease," the authors wrote. "However, treatment decisions were not statistically different and either modality would be appropriate in initial staging, depending on local availability and expertise."

The modalities appear to provide complementary information and more research is needed on the value of combining PET with MRI, the authors advised.