Extramedullary multiple myeloma with central nervous system and multiorgan involvement: Case report and literature review.

Multiple myeloma is a hematologic malignancy due to monoclonal plasma cell proliferation. It is usually confined to the bone marrow, although extramedullary involvement is known to occur in almost any organ system; myelomatous spread to the central nervous system is a rare manifestation of myeloma. Extramedullary disease is thought to be related to hematogenous spread when myeloma cells show decreased cell surface receptor expression, allowing cells to escape from the bone marrow. Disease outside of the bone marrow generally indicates a poor prognosis; central nervous system involvement is associated with a median prognosis of less than 6 months, thereby requiring more aggressive treatment paradigms. We herein describe an unusual case of a patient with extramedullary multiple myeloma with central nervous system and multiorgan involvement. Despite an aggressive treatment strategy, the patient died a few months later after the initial diagnosis. The etiology, diagnostic criteria, clinical presentation, radiological features and differential diagnosis of this patient with extramedullary multiple myeloma are discussed here. The current treatment strategies are also briefly discussed.