MR Imaging Features of Extraspinal Plasmacytoma of Bone

mas, are malignant neoplasms arising from a single clone of plasma cells. They are commonly found in the axial skeleton; especially in the spine, pelvis, and skull and are characterized as expansile osteolytic bone lesions on radiography (1). The MR imaging findings of plasmacytoma or multiple myeloma located in the spine has been well described, but nonspecifically (2, 3). Plasmacytomas usually present as a marrow-replacing process with variable signal intensity on T1-weighted images and high signal intensity on T2-weighted images (1-4). Therefore, it is often indistinguishable from other marrow-replacing processes such as lymphoma or metastasis. For extraspinal lesions, the MR imaging features of plasmacytoma were rarely reported and, to our knowlJ Korean Soc Radiol 2009;61:257-262