A glioblastoma is the most common and aggressive brain tumor. It is malignant and can grow large before becoming symptomatic. The World Health Organization classifies a Glioblastoma multiforme (GBM) as a grade IV astrocytoma. GBMs seldom spread outside the brain, and the cause is not known, but is related to changes in chromosome 17 and inactivation of the p53 tumor suppressor gene. The following steps will show how to diagnose a glioblastoma.
Expect a combination of neurological problems as the surrounding brain is compressed and infiltrated by the GBM. These can vary greatly depending on the size and location of the tumor and may include cognitive difficulties, changes in mental status, headaches, seizures and slight personality changes.
Observe other symptoms of a GBM, including a reduction in blood flow to the brain and increased intracranial pressure.
Perform routine laboratory tests. A GBM usually does not produce significant findings but these are needed to eliminate metabolic disorders and infections.
Run Magnetic Resonance Imaging (MRI) scans with and without contrast as the preferred diagnostic procedure. These tumors usually have low intensity on T1 weighted images and high intensity on T2 weighted images. They usually enhance on contrast and are typically hypodense in the center with a thick contrast enhancing tumor on the outside. Use a Computed Tomography (CT) scan only if an MRI is unavailable or contraindicated.
Confirm a diagnosis of GBM with an open brain or stereotactic brain biopsy.