MR imaging findings of malignant fibrous histiocytoma of bone

The purpose of this study is to assess magnetic resonance (MR) imaging findings of malignant fibrous histiocytoma (MFH) of bone and to evaluate the role of contrast-enhanced MR imaging in the diagnosis of bone MFH. MR imagings of pathologically proven bone MFH in ten patients were reviewed. Enhanced study was also performed with Gd-DTPA. The MR images were evaluated for signal intensity, homogeneity, marginal definition, presence of internal septation, cortical destruction, soft tissue extension, joint involvement and contrast enhancement. Tumors showed iso- or slightly high signal intensity to muscle on T1-weighted images and heterogeneously high signal intensity on T2-weighted images. Four cases showed poor-marginated border on T2-weighted images and four cases had internal septa. Eight of nine patients with intravenous administration of Gd-DTPA showed contrast enhancement, five were heterogeneous and three were homogeneous. All cases showed cortical destruction and soft tissue extension. Five cases showed joint involvement. Bone MFH showed similar MR imaging findings of soft tissue MFH or other malignant bone tumors, but joint involvement was suggestive finding of bone MFH