A Pictorial Review on Extraosseous Manifestations of Multiple Myelomas

Extraosseous involvement of multiple myelomas can be seen clinically or radiologically in approximately 10-20% of patients at the time of initial diagnosis and may develop in an additional 15% of patients over the course of the disease. The condition can arise in any tissue of the body and its presence has been associated with more aggressive disease, a guarded prognosis, or high-dose chemotherapy. Imaging findings of extraosseous multiple myelomas are diverse. They usually show high enhancement on contrast-medium enhanced CT scans, exhibit iso-signal intensity on both T1- and T2- weighted images, and variable 18F-fluorine deoxyglucose (FDG) uptake at PET. The disease may simulate an infectious condition since it may be concurrent with underlying multiple myelomas per se or it may occur during myeloma treatment including stem cell transplantation.