A preliminary diagnosis of schwannoma was made based on the findings from the frozen section; however, immunohistochemical staining of the permanent section revealed strong immunoreactivity for glial fibrillary acidic protein (GFAP) with intermittent S-100 positivity, confirming that the tumor was of the tanycytic type of ependymoma (Figure 3(c)). This evidence concerns the gene GFAP and ependymoma.