Glioblastoma (NORD)

Glioblastoma multiforme, or glioblastoma, is a rare cancerous brain tumor that grows from a helper nerve cell called an astrocyte. It is classified as a type IV astrocytoma, an aggressive type of tumor. Glioblastomas grow very quickly and usually affect the brain or spinal cord in adults impairing normal function.

Glioblastoma is thought to be caused by a genetic change which leads an astrocyte to replicate uncontrollably, forming a tumor. As the tumor grows, it spreads quickly, invading and compressing nearby brain tissue. Although glioblastomas can affect any part of the brain, it most frequently affects the cerebral hemisphere, which controls movement, sensation, memory, cognition, or complex thinking, and language.

Additional glioblastoma risk factors may include: previous radiation treatments to the brain; a history of working in synthetic rubber manufacturing or petroleum refining; or exposure to vinyl chloride or pesticides. Although most people who have had these experiences never develop this disease.

Glioblastoma is more common in individuals between 45 and 70 years of age. Individuals often present with headaches, nausea, vomiting, and seizures. In addition, individuals may have neurologic abnormalities depending on the size and location of the tumor. For example, involvement of the motor cortex can lead to muscle weakness; involvement of the sensory cortex can cause numbness; involvement of the frontal lobe can cause personality changes; involvement of areas responsible for language can affect speech; and involvement of the areas responsible for vision can lead to blindness.

Glioblastoma may also cause brain swelling or block the flow of cerebrospinal fluid, leading to increased pressure within the skull. These dangerous complications do not happen often but, if they do, may require emergency treatment.

An MRI of the brain is usually one of the first tests performed when a brain tumor is suspected. Glioblastoma can be diagnosed when MRI images show a mass that is invading the surrounding brain tissue. Confirmation of this diagnosis requires a biopsy, guided by CT scan or MRI, to obtain a tissue sample. The sample is then examined under a microscope. Additional testing of the tissue sample can be done to identify unique tumor markers which may help determine the best treatment plan.

Though individuals with glioblastoma have a poor prognosis with low long term survival rates, there are treatments available to prolong survival and to improve quality of life.