Neuroimaging of plasmacytoma. A pictorial review

This pictorial review describes the spectrum of CT/MR imaging findings of solitary extramedullary and bone plasmacytomas in different locations related to neuroradiology. Plasmacytoma is considered a counterpart of multiple myeloma that is described as a solitary and discrete mass of monoclonal neoplastic plasma cells. It may arise from osseous (medullary) or extramedullary sites. Isolated extramedullary plasmacytoma is very rare and comprises less than 4% of all plasma cellular diseases of which more than 80% are localized to the submucosal lymphoid tissue of the nasopharynx, nasal cavity and paranasal sinuses. We will demonstrate imaging findings in ten histopathologically proven plasmacytomas in different locations related to neuroradiology. Extramedullary and osseous plasmacytoma show nonspecific CT and MR imaging findings. MR is the preferred modality for evaluation due to better soft tissue contrast. Features that may suggest the diagnosis of plasmacytoma are bulky soft tissue mass and relatively isointense signal on T2-weighted MR images due to high cellularity.