Spinal Magnetic Resonance Imaging of Multiple Myeloma: A Case of Plasmacytoma

Multiple myeloma (MM) is a malignant hemopathy characterized by clonal proliferation of plasma cells, predominantly affecting the axial skeleton. Neurological complications, particularly spinal cord compression, represent a severe and urgent manifestation. We report the case of a 70-year-old patient with known MM, maintained on immunomodulatory therapy, who presented with progressive paraparesis, saddle anesthesia, and urinary retention. Spinal MRI demonstrated diffuse marrow infiltration, a compression fracture of D11, and an infiltrating plasmacytoma of D4 causing spinal cord compression. These findings corresponded to stage III disease according to the Salmon and Durie classification. This case highlights the essential role of MRI in diagnosing and monitoring MM, given its superior sensitivity for detecting marrow infiltration, vertebral fractures, plasmacytomas, and complications such as cord compression. Early and accurate imaging evaluation is indispensable to guide urgent management and improve patient prognosis.