Gliosarcoma with areas of primitive neuroepithelial differentiation and extracranial metastasis

We report a case of gliosarcoma with areas of primitive neuroepithelial dif ferentiation arising in the temporal lobe of a 53-year-old man. The sarcoma tous component of this tumor was perivascular in its distribution and showe d expression of factor VIII-related antigen, smooth muscle actin and CD34. The primitive neuroepithelial component possessed a small cell morphology a nd showed expression of neuronal antigens. Strong expression of p53 was dem onstrated throughout the tumor with only focal weak expression of epidermal growth factor receptor. The tumor developed widespread extraneural metasta ses 5 months after surgical resection of the primary tumor. Histological ex amination of the liver metastases showed them to consist predominantly of t he primitive neuroepithelial component. We believe this to be a novel patte rn of differentiation in a gliosarcoma which in this case was associated wi th an aggressive metastatic potential.