RESUMO
INTRODUCTION: We report the magnetic resonance imaging, angiographic, and immunohistochemical characteristics of a dural leiomyosarcoma in a patient infected with human immunodeficiency virus. METHODS AND RESULTS: A 38-year-old homosexual man presented with a recent history of headaches. Magnetic resonance imaging of the brain revealed an enhancing dural based right lateral wing mass that was thought to be a meningioma. The tumor had a signal intensity similar to the adjacent gray matter on T1-, T2-, and proton-weighted images. Angiography revealed that the tumor was vascular, supplied by the middle meningeal artery, but with contrast puddling as if there were small vascular lakes within the tumor. This evoked the possibility of a cavernous hemangioma. A craniotomy was performed, and the mass was resected. The pathological finding was consistent with a leiomyosarcoma. Immunohistochemistry revealed that the tumor was positive for alpha smooth muscle actin. Repeat testing for human immunodeficiency virus 2 months postoperatively was positive. Dural leiomyosarcomas are thought to take origin from the smooth muscles of the blood vessel walls. Another possible source is pluripotential mesenchymal cells. There may be an association with immunosuppression. CONCLUSION: Primary dural leiomyosarcomas simulate meningiomas on preoperative magnetic resonance images. They should be included in the differential diagnosis of dural based enhancing lesions.