Glioblastoma multiforme is a common and malignant primary intracranial neoplasm. It is classified as a glial tumor because it is composed of poorly differentiated astrocytes. It can develop spontaneously or, less commonly, transform from a lower grade less malignant brain tumor. The majority are located in the cerebral hemispheres, but it rarely begins in the spinal cord or brain stem.

This is a serious condition that requires care from your doctor. If you suspect you have this condition, contact your doctor immediately, as early treatment leads to a more favorable outcome.

Causes

Glioblastoma mutliforme originates from astrocytes, which normally function as structural and supportive cells in the brain. The triggering factors which stimulate a normal functioning astrocyte to develop into a malignant astrocytoma or glioblastoma multiforme are not well understood.

Risk Factors

• GBM is slightly more common in men that women.

• GBM is slightly more common in Caucasians, Latinos, and Asians.

• Low grade astrocytomas, occasionally convert to higher grade tumor, such as anaplastic astrocytoma or glioblastoma multiforme.

• There is an increased incidence of gliomas (including astrocytoma, glioblastoma) associated with several genetic disorders including neurofibromatosis, Von Hippel-Lindau, Li-Fraumeni, and Turcot's syndrome.

• There is also an association between ionizing radiation and astrocytoma.

• Popular concerns regarding electromagnetic radiation and cellular phone use have not been supported with epidemiologic studies.

Symptoms

• New onset headaches – more than 30% of patients

• New onset seizures – 30-60% patients

• Progressive cognitive dysfunction: depending on the location of the tumor, focal deficits affecting vision, language, motor function, sensation are reported

Diagnosis

After taking a complete history of your symptoms and completing a physical exam, your doctor may also use the following tests:

• CT Scan – a type of x-ray that uses a computer to make pictures of structures inside the brain

• MRI Scan – a test that uses magnetic waves to make pictures of structures inside the brain

• Electroencephalogram (EEG) – a test that records the brain's activity by measuring electrical currents through the brain

• Brain Biopsy – removal of a sample of brain tissue to test for abnormalities in the brain

• Spinal Tap – removal of a small amount of cerebrospinal fluid to check for abnormalities in the brain

• Positron Emission Tomography (PET) Scan – produces images that show the amount of functional activity in the living tissue being studied

Treatment

Surgery is often performed to confirm diagnosis and relieve headache, but complete resection is impossible. Radiation treatment is used to further decrease the size of the tumor, usually by about 25%. Chemotherapy also increases survival time and quality of life. Steroids to suppress swelling, antiseizure medication to suppress seizures, and pain medications are routinely used to help patients.

Unfortunately, overall prognosis is poor, and even with aggressive treatment, few patients survive more than five years after diagnosis. However, there is evidence that current medical and surgical intervention increases life expectancy and improves quality of life.

Prevention

As the causes of GBM are unknown, there are no preventive measures.

RESOURCES:

American Brain Tumor Association
http://www.abta.org

American Cancer Society
http://www.cancer.org

Brain Tumor Society
http://www.tbts.org

National Brain Tumor Foundation (NBTF)
http://www.braintumor.org

National Cancer Institute
http://www.cancer.gov

CANADIAN RESOURCES:

Brain Tumor Foundation of Canada
http://www.btfc.org/

Canadian Cancer Society
http://www.cancer.ca

References:

Adult brain tumors: treatment: glioblastoma. National Cancer Institute website. Available at: http://www.cancer.gov/cancertopics/pdq/treatment/adultbrain/HealthProfessional/page9. Accessed September 29, 2005.

Brain tumor-adults. Medline Plus Medical Encyclopedia website. Available at: http://www.nlm.nih.gov/medlineplus/ency/article/007222.htm. Accessed September 29, 2005.

Brain tumors. The Merck Manual of Medical Information: Second Home Edition Online website. Available at: http://www.merck.com/mmhe/sec06/ch088/ch088b.html. Accessed September 29, 2005.