A prospective study comparing whole-body skeletal X-ray survey with 18F-FDG-PET/CT, 18F-NaF-PET/CT and whole-body MRI in the detection of bone lesions in multiple myeloma patients.

Background: For decades, the most widely used imaging technique for myeloma bone lesions has been a whole-body skeletal X-ray survey (WBXR), but newer promising imaging techniques are evolving.

Purpose: To compare WBXR with the advanced imaging techniques 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT), 18F-sodium fluoride (NaF) PET/CT and whole-body magnetic resonance imaging (WB-MRI) in the detection of myeloma bone lesions.

Material and Methods: Fourteen patients with newly diagnosed multiple myeloma were prospectively enrolled. In addition to WBXR, all patients underwent FDG-PET/CT, NaF-PET/CT, and WB-MRI. Experienced specialists performed blinded readings based on predefined anatomical regions and diagnostic criteria.

Results: In a region-based analysis, a two-sided ANOVA test showed that the extent of detected skeletal disease depends on the scanning technique ( P  < 0.0001). Tukey's multiple comparison test revealed that WB-MRI on average detects significantly more affected regions than WBXR ( P  < 0.005), FDG-PET/CT ( P  < 0.0001), and NaF-PET/CT ( P  < 0.05). In a patient-based analysis, a Cochran's Q test showed that there are no significant differences in the proportion of patients with bone disease detected by the different scanning techniques ( P  = 0.23). Determination of intrareader variability resulted in Kappa coefficients corresponding to moderate (FDG-PET/CT) and substantial agreement (WB-MRI, WBXR, NaF-PET/CT).

Conclusion: WB-MRI detects on average significantly more body regions indicative of myeloma bone disease compared to WBXR, FDG-PET/CT, and NaF-PET/CT. The lack of significance in the patient-based analysis is most likely due to the small number of study participants.