Overview and Facts about Glioma
A glioma is a type of brain tumor that originates from the glial cells of the brain. Glial cells help support and protect neurons, specialized cells of the nervous system that transmit chemical and electrical signals between the brain and other parts of the body.
There are three main types of glial cells — astrocytes, oligodendrocytes and ependymal cells — that can produce a tumor. An astrocyte produces astrocytoma tumors (including glioblastoma), oligodendrocytes produce oligodendroglioma tumors and ependymoma tumors come from ependymal cells.
There are different grades of gliomas, indicating their aggressiveness and growth potential. Gliomas make up about 74 percent of malignant brain tumors.
Signs and Symptoms of Glioma
Symptoms of a glioma vary depending on type, size and location (or which glands or nerves). Signs of an astrocytoma tumor include:
- Changes in mood and personality
- Changes in the ability to think and learn
- Double or blurred vision
- New seizures and speech difficulty
- Persistent headaches
- Vomiting and loss of appetite
Signs of an oligodendroglioma tumor include:
- Altered vision or visual hallucinations
- General changes in brain function
- Headaches that are worse in mornings, not alleviated by painkillers and accompanied by nausea and vomiting
- Muscular weakness and loss of control of bodily movements
- Seizures, vertigo or nausea
Signs of an ependymoma tumor include:
- Bowel or bladder problems
- Eye problems, such as double or blurry vision
- General pain, weakness or numbness in an arm or leg and difficulty walking
- Headaches, dizziness and balance problems
- Nausea and vomiting
Causes and Risk Factors of Glioma
The exact cause of gliomas is not known. Gliomas are most often seen in adults between the ages of 45 and 65 and are slightly more likely to occur in men than in women. There are also several genetic conditions that predispose an individual to develop gliomas.
Tests and Diagnosis of Glioma
Diagnosis of a glioma includes a neurological exam to check brain, spinal cord and nerve function. Testing evaluates a person’s mental status and coordination as well as how well their muscles, reflexes and senses work. Magnetic resonance imaging (MRI) and computed tomography (CT scan) are the most common imaging scans used to diagnose brain tumors.
When imaging tests confirm the presence of a tumor, a biopsy is performed to determine the type of glioma.
Treatment and Care of Glioma
Treatment depends on the type, grade and location of the tumor. Gliomas are referred to as "low grade" (grades I or II) or "high grade" (grades III or IV), based on the tumor’s growth potential and aggressiveness. Neurological surgery to remove as much of the tumor as possible is the most common initial treatment for gliomas. Adjuvant treatments including radiation therapy and chemotherapy are given based on type of glioma. Outcomes depend on type of glioma and grade.
Medications to improve symptoms and neurologic function can be prescribed. Corticosteroids can help reduce swelling in the brain caused by the tumor and anticonvulsants can control or prevent seizures.