A<unk>  is a type of primary central nervous system (CNS) tumor that arises from<unk> al cells.  The most common site of involvement of<unk> s is the brain, but<unk> s can also affect the spinal cord or any other part of the CNS, such as the optic nerve.<unk> s were reported as early as the 1850s. Retinal<unk> s were most commonly reported because they were easier to detect and sample in the absence of advanced imaging and surgical techniques.<unk>  may be classified into several subtypes based on the type of cell, grade, and location. The pathogenesis of cerebral<unk>  involves invasion of the tumor cells into the adjacent normal brain tissue. The gross and histopathological appearance of<unk>  varies with the tumor grade and type.<unk>  must be differentiated from primary CNS lymphoma, cerebral metastases, meningioma, brain abscess, cavernous malformation, stroke, acute disseminated encephalomyelitis, cavernous sinus syndrome, intracranial hemorrhage, gerstmann syndrome, spinal tuberculosis, hamartoma, germinoma, teratoma, piloid<unk> osis, and progressive multifocal leukoencephalopathy. The incidence of<unk>  is estimated to be 4.9 cases per 100,000 individuals in the US. Patients of all age groups may develop<unk> . Males are more commonly affected with<unk>  than females. It usually affects individuals of the caucasian race. African american, latin american, and asian individuals are less likely to develop<unk> . Common risk factors in the development of<unk>  are occupational factors, environmental factors, genetic factors, and viruses. Common complications of<unk>  include brain herniation, coma, metastasis, and recurrence. The prognosis of<unk>  varies with the grade of tumor. The 1-year and 2-year survival rate of patients with malignant<unk>  is approximately 50% and 25%, respectively. Common symptoms of<unk>  include morning headaches, nausea and vomiting, seizures, drowsiness, changes in speech, difficulty in swallowing, vision changes, abnormal eye movements, changes in personality, memory loss, loss of balance, difficulty in walking, weakness in extremities, numbness in extremities, pain in extremities, and loss of appetite. The CT scan and MRI findings of<unk>  vary with the tumor grade and type. The predominant therapy for<unk>  is surgical resection. Adjunctive chemotherapy and radiation may be required.
Glioma
Astrocytoma
Meningioma
Ameloblastoma
Glioblastoma multiforme
Coma
Hemangioblastoma
High grade astrocytoma