Prognostic value of [18F]fluorodeoxyglucose-PET/MRI(CT) novel interpretation criteria (IMPeTUs) in multiple myeloma.

Purpose [18F]fluorodeoxyglucose (FDG)-PET is a powerful tool to evaluate prognosis in multiple myeloma (MM). The development of systematic and reproducible standard interpretation criteria is crucial for the effective application of FDG-PET in MM. A new set of criteria-Italian Myeloma criteria for PET Use (IMPeTUs)-has standardized PET evaluation in MM. However, the prognostic value of IMPeTUs score remains unknown.Methods A total of 58 patients with newly diagnosed multiple myeloma (NDMM) who underwent both [18F]FDG-PET/MRI and PET/CT examinations at diagnosis were enrolled (ChiCTR1900022597). All patients completed a 42-month follow-up. The prognostic value of the PET/MRI (or PET/CT) IMPeTUs score in predicting progression-free (PFS) and overall (OS) survival was compared with that of individual laboratory parameters and the maximum standardized uptake value (SUVmax). Kaplan-Meier method was used for survival analysis. Univariate and multivariate analyses of prognostic factors were conducted using Cox regression.Results ROC curves demonstrated that the area under the curve for the PET/MRI IMPeTUs score was 0.760, exceeding that of the PET/CT IMPeTUs score (0.711), PET/CT BM SUVmax (0.649), PET/MRI BM SUVmax (0.575), bone marrow plasma cells (0.500), and β2-microglobulin (0.501). Univariate analysis and Kaplan-Meier analysis showed that a PET/MRI IMPeTUs score ≥ 13 and PET/CT IMPeTUs score ≥ 10 were significantly associated with worse PFS. Cox multivariate analysis showed that a PET/MRI IMPeTUs score ≥ 13 was an independent risk factor for PFS.Conclusion IMPeTUs standardized [18F]FDG-PET/MRI and PET/CT readings in MM. The IMPeTUs score is crucial for predicting MM prognosis, performing better than SUVmax and clinical indicators.Clinical Trial Registration ChiCTR1900022597, Registered on 18 April 2019.