Imaging in multiple myeloma: How? When?

Bone disease is the most frequent feature of multiple myeloma (MM) and represents a marker of end-organ damage, used to establish the diagnosis and to dictate the immediate need of therapy. For this reason, imaging plays a significant role in the management of MM patients. Although conventional radiography has traditionally been the standard imaging modality, its low sensitivity in detecting osteolytic lesions and inability to evaluate response to therapy has called for the use of more sophisticated techniques, such as whole body low dose computed tomography (WBLDCT), whole body magnetic resonance imaging (WBMRI), and 18F-fluorodeoxyglucose positron emission tomography (FDG-PET/CT). In this review, the advantages, indications of use, and applications of the three different techniques in the management of patients with MM in different settings will be discussed. The European Myeloma Network (EMN) and the European Society for Medical Oncology (ESMO) guidelines have recommended whole body low-dose CT (WBLDCT) as the imaging modality of choice for the initial assessment of MM-related lytic bone lesions. MRI is the gold-standard imaging modality for detection of bone marrow involvement, while PET/CT provides valuable prognostic data and is to date the preferred technique in assessment of response to therapy. Standardization of most of the techniques is on-going.