抄録
A six year-old intact female miniature poodle dog, was presented with a soft mass of the forehead region. Computed tomography identified generalized frontal bone loss and a large extracranial mass, which had low-attenuation area of hemorrhagic necrosis with septation and enhancement of solid components. The mass was isointense in T1-weighted images except fluid part and hyperintense in T2-weighted images with lobulated by low-signal septa in magnetic resonance imaging. The surgery was performed to remove the mass, and histopathologic examination revealed that mass was consistent with undifferenciated pleomorphic sarcoma (malignant fibrous histiocytoma). The dog died from rapidly recurrent mass and severe pulmonary metastasis.