Glioblastoma multiforme (GBM) is the most aggressive form of the primary brain tumors known collectively as gliomas. These tumors arise from the supporting, glial cells of the brain during childhood and in adults. These growths do not spread throughout the body like other forms of cancer, but cause symptoms by invading the brain.

Glioblastoma multiforme (GBM) is by far the most common and most malignant of the glial tumors, accounting for approximately 12-15% of all intracranial neoplasms and 50-60% of all astrocytic tumors. In most European and North American countries, incidence is approximately 2-3 new cases per 100,000 people per year.

Composed of poorly differentiated neoplastic astrocytes, glioblastomas primarily affect adults, and they are located most commonly in the cerebral hemispheres. The aetiology of gliomas remains unknown (the only consistently identified risk factor is chronic exposure to petrochemicals).

Glioblastomas can be classified as primary or secondary. Primary GBMs account for the vast majority

of cases (60%) in adults older than 50 years.

Secondary GBMs (40%) typically develop in younger patients (<45 y) through malignant progression from a low-grade astrocytoma (WHO grade II) or anaplastic astrocytoma (WHO grade III). The time required for this progression varies considerably, ranging from less than 1 year to more than 10 years, the mean interval being 4-5 years.

The treatment of patients with malignant gliomas is palliative and encompasses surgery, radiotherapy, and chemotherapy.

1. Jeffrey Bruce, MD, Director of Bartoli Brain Tumor Laboratory, Director of Brain Tumor Tissue Bank, Professor of Neurological Surgery, Department of Neurosurgery, Columbia University College of Physicians and Surgeons
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