Gliosarcoma : MR features

Our goal was to characterize the MR features of pathologically documented gliosarcoma and to determine if these features help differentiate gliosarcoma from other intracranial neoplasms. MR studies of six patients with pathologically documented gliosarcoma were retrospectively analyzed. The tumors tended to be well defined lesions demonstrating either an inhomogeneous or cystic appearance with surrounding vasogenic edema. All tumors were characterized as primarily intraaxial but abutting a dural surface. On T2-weighted images, all tumors were of intermediate signal intensity with surrounding edema. The signal intensity of the tumor was similar to gray matter but was hypointense relative to other glial neoplasms. Postcontrast T1-weighted images showed intense tumor enhancement, often with a ring-like appearance. The isointense component on the T2-weighted images corresponded to this area of intense enhancement. Gliosarcoma exhibits some characteristic MR features. It should be included in the differential diagnosis of any tumor that appears to be intraaxial but abuts a dural surface and is much less hypointense on T2-weighted images than other glial neoplasms.