Onkológia 6/2022

Multiple myeloma and whole body imaging techniques: what, when and why?

Multiple myeloma is a hematologic malignancy characterized by clonal proliferation of the plasma cells in the bone marrow with the production of abnormal immunoglobulins leading to the destruction of mineralized bones, kidney impairment, anemia, and hypercalcemia. Skeletal damage is one of the most frequent clinical symptoms of myeloma and is a criterion for treatment initiation. The development of new imaging techniques increased the importance of skeleton imaging in multiple myeloma. International working groups like European Myeloma Network (EMN), European Society of Medical Oncology (ESMO), and International Myeloma Working Group (IMWG) defined the role and utilization of the whole-body imaging in the management of patients with plasma cell dyscrasias. Whole-body low-dose CT (WB LDCT) is currently the most suitable method for detecting osteolytic lesions in patients suspected of multiple myeloma and substitutes conventional radiography. Whole-body MRI (or axial MRI in case WB MRI is unavailable) should be added in all patients with smoldering myeloma if WB LDCT did not detect osteolytic lesions. MRI can detect occult lesions in the bone marrow, indicating the necessity of treatment initiation. PET/CT is less precise in the detection of diffuse bone marrow infiltration compared with MRI, still it is the best method for evaluation of the response to treatment, confirmation of complete remission, and further follow-up of patients. There is an ongoing effort to unify the interpretation and reporting of findings of imaging techniques in patients with myeloma and other plasma cell dyscrasias.

Keywords: multiple myeloma, monoclonal gammopathy of undetermined significance, osteolytic lesions, whole body imaging techniques, focal bone marrow lesions