Glioblastoma For more information, please visit our Comprehensive Brain & Spinal Tumor site What do I have? Known as Glioblastoma Multiforme, Malignant Gliomas and Grade 4 Gliomas,Glioblastomas are brain tumors that develop from brain cells called astrocytes. Tumors developing from astrocytes can be low grade astrocytomas, anaplastic astrocytomas or glioblastomas, the most aggressive type of brain tumor in adults. What does it do? The brain has specialized areas that help us control individual functions, so if a tumor develops in the part of the brain that controls the right leg, you may have weakness, numbness, or seizures in that leg. If a tumor develops in the part of the brain that controls language, you may have trouble speaking or understanding. Most tumors are found because they cause a symptom that leads your doctors to check an MRI or CT of the brain. How long have I had it? Glioblastomas are the most aggressive brain tumors, sometimes starting out as fast growing tumors, and sometimes developing from slow growing tumors that become more and more aggressive over many years. While there can be clues in the tumor itself that can help us guess how quickly it has been growing, these are only clues, and most times we can't tell how long a brain tumor has been there. Can it be cured? Glioblastomas are usually not curable, but are treatable. We do our best to control the tumor and keep it from growing and causing more symptoms using many different tools including surgery, radiation and chemotherapy. What caused it? No one knows for sure what causes glioblastomas, although exposure to radiation may increase the likelihood of developing a brain tumor. While scientists have looked at other possible causes such as aspartame (Nutrasweet), cell phones, and power lines, no one has been able to show that any of these clearly cause glioblastomas.