Radiological imaging in multiple myeloma: review of the state-of-the-art

Multiple myeloma is a type of blood cancer arising from the uncontrolled clonal proliferation of malignant plasma cells resulting in impaired hematopoiesis, hyper production of monoclonal protein, bone tissue destruction leading and renal system alterations up to kidney failure. The aim is to review the state-of-the-art of radiological imaging in multiple myeloma. Radiological techniques as well as the advancements in imaging technology have been reviewed and summarized. The main radiological findings of different imaging techniques in patients suffering from multiple myeloma are also illustrated. Different radiological techniques provide structural and functional data. In the last years, conventional skeletal survey has gradually lost its utility and it has been replaced by whole body low-dose computed tomography which allows to identify also small lytic lesions, the medullary and the extramedullary involvement. Nowadays, magnetic resonance is the most sensitive imaging technique for detecting of skeletal as well as medullary involvement in patients with multiple myeloma. Thanks to the multiparametric evaluation (morphological, diffusion weighted and perfusion imaging sequences) and to the quantitative analysis, magnetic resonance imaging is proved to be useful in the early evaluation of response to therapy. Finally, positron emission tomography has greater sensibility compared to computed tomography as it provides quantitative data; however, the lower expression levels of the specific gene involved in the glycolysis pathway are associated with false-negative results with consequent underestimation of the disease. The only use of the advanced combined multimodal imaging allows a better evaluation, staging and early assessment of treatment response in patients with multiple myeloma.