Astrocytomas are primary central nervous system tumors that arise primarily in an rarely spread away from the CNS parenchyma contained within the cranial vault. Astrocytomas "are CNS neoplasms in which the predominant cell type is derived from an immortalizedastrocyte and account for roughly 75% of neuroepithelial tumors. In 1993 the World Health Organization (WHO) established a four-tiered histologic grading guideline for astrocytomas in an effort to eliminate confusion regarding diagnoses. The low grade astrocytomas (I & II) are among the least common of all reported brain tumors, less than 6%, while the highest grade (IV), also known as glioblastoma multiforme (GBM), is the most common primary CNS malignancy and second most frequent brain tumor. Despite the comparatively low incidence of astrocytomas to other human cancers, the higher grades (III & IV) represent disparate mortality rates. Median survival of GBM victims who forgo treatment is approximately 90 days, and even with aggressive surgical, radio- and chemo- therapies is only extended to about twelve months, while long term survival (at least five years) falls under 3%.