18F-FDG PET/CT is useful for determining survival outcomes of patients with multiple myeloma classified as stage II and III with the Revised International Staging System

PurposeThis study evaluated the prognostic role of F-18-FDG PET/CT at baseline in patients with newly diagnosed multiple myeloa (MM) and evaluated the prognostic relevance of F-18-FDG PET/CT for each stage according to the Revised International Staging System (R-ISS). Method We retrospectively analyzed the records of 167 patients with newly diagnosed MM. F-18-FDG PET/CT was performed prior to induction therapy in patients with newly diagnosed MM. Results In the total cohort, the presence of more than three hypermetabolic focal lesions (FLs) or extramedullary disease (EMD) on baseline PET/CT was associated with significantly inferior progression-free survival (PFS) and overall survival (OS) than other patients. Because most patients (91%) with EMD had more than three FLs, PET/CT positivity was defined as the presence of more than three FLs or the presence of EMD. In multivariate analyses, PET/CT positivity was an independent predictor of PFS and OS in all patients. Fifty-five patients (46.1%) with R-ISS II were PET/CT-positive at baseline and had significantly shorter PFS and OS. PET/CT positivity was also correlated with poor PFS and OS in patients with R-ISS III. Conclusion F-18-FDG PET/CT was an independent predictor of survival outcomes in patients with newly diagnosed MM. In addition, performing F-18- FDG PET/CT at diagnosis may be useful for determining the survival outcomes of MM patients with R-ISS II and III.