Primary intracerebral osteosarcoma.

A 64-year-old man was admitted because of a rapidly progressive left side hemiparesis. A computed tomography scan showed a right side intrathalamic mass, partially calcified. Surgical specimen proved to be an osteosarcoma. The patient died 3 days later from an acute myocardial infarct. Autopsy failed to discover any other significant lesion. A review of the literature disclosed that this case might be the second published primary intracerebral osteosarcoma and the first with immunocytochemical analysis.