Glioblastoma Multiforme
(GBM; Brain Tumor; Malignant Astrocytoma)
Definition
Glioblastoma multiforme (GBM) is the most common glioma—a type of brain cancer. This cancer starts in the glial cells, which are cells that help nerve cells work.
This condition can develop suddenly. It can also develop from a lower grade, less cancerous brain tumor. Most cases are located in the cerebral hemisphere of the brain. The cancer can also begin in the spinal cord or brain stem.
Brain Tumor
Causes
GBM originates from astrocytes, which are a type of glial cell. The factors that cause normal-functioning astrocytes to become cancerous is not well understood.
Risk Factors
Factors that increase your chances of developing GBM include:
- Age: over 50 years old
- Ethnicity: Caucasians, Hispanics, Asians
- Having a low-grade brain tumor, which occasionally develops into a higher-grade tumor
-
Having one of the following genetic disorders:
- Neurofibromatosis
- Tuberous sclerosis
- Von Hippel-Lindau disease
- Li-Fraumeni syndrome
- Turcot's syndrome
- Having had radiotherapy
- Working in the synthetic rubber or petroleum refining industries
- Exposure to vinyl chloride or pesticides
- Having had computed tomography (CT) scans during childhood
Symptoms
Symptoms include:
- New onset headaches—more than 30% of patients
- New onset seizures—20% to 30% patients
- Progressive cognitive dysfunction—depends on the location of the tumor; problems with vision, language, motor function, or sensation may occur
- Progressive neurological deficits, including weakness
- Personality changes
- Behavioral changes, development of inappropriate behaviors
- Memory loss
Diagnosis
Your doctor will ask about your symptoms and medical history. A physical exam will be done.
Images and scans may be taken of your brain. This can be done with:
- CT scan
- MRI scan
- Functional MRI (fMRI)
- Positron emission tomography (PET) scan
Your brain activity may be measured. This can be done with:
- MRS scan
- Electroencephalogram (EEG)
Your bodily fluids and tissues may be tested. This can be done with:
Treatment
Surgery is often done to confirm diagnosis and relieve headache, but doctors cannot completely remove the cancer. Other types of treatment may include:
- Radiation treatment is used to further decrease the size of the tumor.
- Chemotherapy is used to increase survival time and quality of life.
- Steroids to suppress swelling, antiseizure medication to suppress seizures, and pain medications are also used.
Even with aggressive treatment, few patients survive more than five years after diagnosis. However, there is evidence that medical and surgical intervention can increase life expectancy and improve quality of life.
A multi-disciplinary approach is important for you and your family. This approach may involve:
- Support group
- Psychotherapy and psychiatry
- Pain management
- Hospice care
Prevention
As the causes of GBM are unknown, there are no preventive measures.
American Brain Tumor Association
National Brain Tumor Society
Brain Tumor Foundation of Canada
Canadian Cancer Society
Adult brain tumors treatment (PDQ). National Cancer Institute website. Available at: http://www.cancer.gov/cancertopics/pdq/treatment/adultbrain/healthprofessional. Updated May 14, 2013. Accessed June 11, 2013.
Brain tumors. The Merck Manual of Medical Information: Second Home Edition Online website. Available at: http://www.merck.com/mmhe/sec06/ch088/ch088b.html. Updated February 2008. Accessed June 11, 2013.
Glioblastoma multiforme. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed/what.php. Updated June 3, 2013. Accessed June 11, 2013.
Last reviewed June 2013 by Mohei Abouzied, MD; Michael Woods, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.


