may improve overall survival in patients with the most malignant primary brain tumors, it does so in only about 20 percent of patients. Chemotherapy is often used in young children instead of radiation, as radiation may have negative effects on the developing brain. The decision to prescribe this treatment is based on a patient's overall health, type of tumor, and extent of cancer. The toxicity and many side effects of the drugs, and the uncertain outcome of chemotherapy in brain tumors puts this treatment further down the line of treatment options with surgery and radiation therapy preferred. UCLA Neuro-Oncology publishes real-time survival data for patients with a diagnosis of glioblastoma multiforme. They are the only institution in the United States that displays how brain tumor patients are performing on current therapies. They also show a listing of chemotherapy agents used to treat high-grade glioma tumors. Genetic mutations have significant effects on the effectiveness of chemotherapy. Gliomas with IDH1 or IDH2 mutations respond better to chemotherapy than those without the mutation. Loss of chromosome arms 1p and 19q also indicate better response to chemoradiation. Other A shunt may be used to relieve symptoms caused by intracranial pressure, by reducing the build-up of fluid (hydrocephalus) caused by the blockage of the free flow of cerebrospinal fluid. Prognosis The prognosis of brain cancer depends on the type of cancer diagnosed. Medulloblastoma has a good prognosis with chemotherapy, radiotherapy, and surgical resection while glioblastoma multiforme has a median survival of only 12 months even with aggressive chemoradiotherapy and surgery. Brainstem gliomas have the poorest prognosis of any form of brain cancer, with most patients dying within one year, even with therapy that typically consists of radiation to the tumor along with corticosteroids. However, one type, focal brainstem gliomas in children, seems open to exceptional prognosis and long-term survival has frequently been reported. Prognosis is also affected by presentation of genetic mutations. Certain mutations provide better prognosis than others. IDH1 and IDH2 mutations in gliomas, as well as deletion of chromosome arms 1p and 19q, generally indicate better prognosis. TP53, ATRX, EGFR, PTEN, and TERT mutations are also useful in determining prognosis. Glioblastoma multiforme Glioblastoma multiforme (GBM) is the most aggressive (grade IV) and most common form of a malignant brain tumor. Even when aggressive multimodality therapy consisting of radiotherapy, chemotherapy, and surgical excision is used, median survival is only 12–17 months. Standard therapy for