Imaging in multiple myeloma.

Multiple myeloma (MM) is the second most common adult hematologic malignancy, characterized by clonal proliferation of malignant plasma cells mostly in the bone marrow. The presence of destructive changes of the mineralized bone is a hallmark feature of the condition and a sign of end-organ damage. Due to this, imaging plays an integral role in the diagnosis, prognostication, and treatment monitoring of patients undergoing therapy for MM as well as surveillance of patients with early-stage disease. While conventional radiography has traditionally been the mainstay of initial evaluation of patients suspected of having MM, the advent of more sensitive imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) have taken its place in assessing patients. While either CT alone or as part of a PET/CT examination is the initial radiographic method of choice, MRI remains the gold-standard modality in assessing bone marrow involvement, especially in early disease stages. PET/CT also provides valuable information regarding assessment of response to therapy and extramedullary manifestations of the disease. There is however increasing evidence that functional MRI techniques, albeit limitedly available, might be superior to PET/CT for treatment monitoring. This review summarizes current knowledge on the use of different imaging techniques in monoclonal plasma cell disorders and discusses future developments in this area of research.