Subependymoma with prominent rosenthal fiber formation: case report.

A 62-year-old woman presented with a rare case of subependymoma associated with prominent Rosenthal fibers located in the left lateral ventricle manifesting as right hemiparesis and mild motor aphasia. The tumor was well demarcated and consisted of clusters of round nuclei embedded in an abundant gliofibrillary matrix with some microcysts and prominent Rosenthal fibers. Immunohistochemically, the tumor stained positively for glial fibrillary acidic protein and negatively for synaptophysin. This case of subependymoma containing Rosenthal fiber formation is very unusual.