Figure 2: SEGA in a patient with tuberous sclerosis. (A) SEGA (arrow) causing hydrocephalus. (B) Same tumor (arrow) after 3 months of therapy with oral sirolimus. (C) Pathology (hematoxylin and eosin) shows a low-grade tumor composed of cells with monomorphic round nuclei and abundant eosinophilic cytoplasm with low Ki67 (inset) and (D) focal GFAP positivity consistent with SEGA. Unpublished data. GFAP: Glial fibrillary acidic protein, R: Right, SEGA: Subependymal giant cell astrocytoma