Splenic T2 signal intensity loss on MRI is associated with disease burden in multiple myeloma

This study aims to evaluate correlations between spleen signal changes in different MRI sequences and bone marrow plasma cell infiltration as potential indicator of disease burden in multiple myeloma (MM) patients. We retrospectively analyzed 45 patients with newly diagnosed MM that underwent whole-body MRI with axial DWI at b-values 50 (b50) and 800 (b800), and coronal T1 and T2 fast spin-echo (T2-TSE) imaging. A subcohort of 39 patients had concomitant [ F]FDG PET/CT. The spleen was segmented in all MRI sequences and signal intensities were normalized. MR signal intensities and ADC values were correlated with bone marrow plasma cell infiltration from biopsy, laboratory markers (Beta 2-microglobulin, M-Protein, Red blood count (RBC), Hemoglobin, Hematocrit, Total protein, Creatinine), clinical data (ISS stages, high-risk chromosomal aberrations), and standardized uptake value (SUV) in the spleen as well as spleen-to-liver and spleen-to-blood pool SUV ratios on [ F]FDG PET-CT. Bone marrow plasma cell infiltration was negatively correlated with (normalized) mean splenic signal intensity on DWI-b50, DWI-b800, and T2-TSE images (r = -0.64, p