<prompt> Most common site of sub ependymal astrocytoma giant cellTrigone of lateral ventricleForamen of munroTemporal horn of lateral ventricle4th ventricle  <response>: Subependymal giant cell astrocytoma SEGA, SGCA, or SGCT is a low-grade astrocytic brain tumor astrocytoma that arises within the ventricles of the brain. It is most commonly associated with tuberous sclerosis complex TSC. Although it is a low-grade tumor, its location can potentially obstruct the ventricles and lead to hydrocephalus Subependymal giant cell astrocytoma SEGA is a slowly growing tumor of unknown histogenesis mainly arising in the periventricular regions adjacent to the foramen of Monro which causes increased intracranial pressure, seizures, and focal neurologic signs Ref Harrison20th edition pg 2456 