الفهرس 
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Abstract
Astrocytic tumors are the most common tumors of the central nervous system, constituting 67.10% of total CNS tumors and 0.52% of total malignancy. According to the registry of the NCI, Cairo University, the ranking of adult CNS malignant tumors is 12 but for pediatrics,is 7. American Cancer Society (ACS) estimated that,
approximately 13.070 people will die from these
malignant tumors. This type of cancer accounts for 1.3% of all cancers and 2.2% of all cancer- related death.
According to WHO classification system, astrocytoma can be divided into four different grades: pilocytic astrocytoma (WHO grade I), diffuse astrocytoma (WHO grade II), anaplastic astrocytoma (WHO grade III) and glioblastoma multiforme (WHO grade IV).
Glioblastoma multiforme (GBM) is the most common and one of the most aggressive primary brain tumors,because of its aggressive nature, its treatment usually involves a combinationof surgery, radiation therapy and chemotherapy. Althougth all patients receive multidisciplinary treatment, the median survival time for patients with GBM is only 1 year.