Teaching Case

Chronic headache with recent personality changes.

Admitted for seizures and signs of increased intracranial pressure . An MRI was performed. The diagnosis of glioblastoma multiforme ( GBM) was confirmed by stereotaxic brain biopsy.

Glioblastoma multiforme (GBM) is the most common of all the primary intracranial tumors, representing 15% to 50% of these lesions. It is the most malignant of all glial neoplasms. GBM can be found at any age but usually occur in patients over 50 and are rare under 30. They are usually large heterogenous masses with central necrosis, thick irregular walls and increased vascularity. Mass effect and edema are usually striking. Various symptoms occur with GBM, including seizures, focal neurologic deficits and strokelike syndroms. The usual location of these tumors are the deep cerebral white mater, particularly the frontal and temporal bones. Posterior fossa GBM are rare. MR reflects the heterogenous, multiforme nature of these lesions. T1 weighted images show a poorly delineated mixed-signal mass with necrosis and thick irregular wall. T2 weighted studies show a very heterogenous mass with mixed signal , cellular components , necrosis and hemorrhage of varying ages. Marked , heterogenous contrast enhancement is present in the majority of GBM. Hemorrhage of different ages are often present. Tumor margins often blend imperceptly with the surrounding edema. Although MR can help to anticipate the correct diagnosis, a pathological proof is needed and stereotactic or open biopsy should be performed whenever possible such as the minor hemisphere or cerebellum.