Glioma
A tumor arising from the brain or spinal cord's supporting cells
Quick Facts
- Type: Brain or spinal cord tumor
- Grows from: Glial (supporting) cells
- Grades: Low-grade (slow) to high-grade (aggressive)
- Common symptoms: Headache, seizures, focal weakness
Overview
A glioma is a tumor that begins in the glial cells, the supporting cells that surround and protect the nerve cells of the brain and spinal cord. Gliomas are among the most common tumors that start within the brain itself. They include several types, such as astrocytomas, oligodendrogliomas, and ependymomas, named for the kind of glial cell involved.
Gliomas vary widely. Some are low-grade and slow-growing, while others, such as glioblastoma, are high-grade and aggressive. Because they grow within the confined space of the skull or spine, even a benign-behaving glioma can cause symptoms by pressing on nearby tissue. Treatment and outlook depend heavily on the tumor's type, grade, genetic features, and location, and are guided by a specialized care team.
Symptoms
Symptoms depend on the tumor's size, grade, and location in the brain or spinal cord.
- Headaches that are new, persistent, or worse in the morning
- Seizures, which are a common first sign
- Weakness or numbness on one side of the body
- Problems with speech, vision, balance, or coordination
- Personality, memory, or thinking changes
- Nausea and vomiting, especially with raised pressure in the brain
A first-ever seizure, sudden severe headache, sudden weakness or numbness, or trouble speaking should be treated as an emergency, as these can also signal other serious conditions such as a stroke.
Causes
The cause of most gliomas is unknown. They develop when glial cells acquire changes that make them grow uncontrollably.
- Gene changes in the tumor cells: These drive abnormal growth and also help classify the tumor.
- Radiation exposure: Previous high-dose radiation to the head is a recognized risk factor.
- Inherited syndromes: Rare genetic conditions, including neurofibromatosis, can increase the risk of certain gliomas.
Gliomas are not contagious, and in most people no specific cause can be identified.
Risk Factors
- Previous radiation therapy to the head
- Increasing age for many high-grade gliomas, though some types occur in children and young adults
- Certain inherited conditions, such as neurofibromatosis or other rare tumor syndromes
- A family history of brain tumors in a small number of cases
Diagnosis
Diagnosis combines imaging with tissue analysis.
- MRI scan: The main imaging test, showing the tumor's location, size, and features; CT may be used in urgent settings.
- Neurological examination: Testing strength, sensation, reflexes, vision, and coordination.
- Biopsy or surgery: A tissue sample is examined to determine the tumor type and grade, which guides treatment.
- Molecular testing: Genetic analysis of the tumor that increasingly shapes diagnosis and treatment choices.
Treatment
Treatment is tailored to the tumor's type, grade, genetic features, and location, as well as the person's overall health.
- Surgery: Often the first step, to remove as much tumor as safely possible and obtain tissue for diagnosis.
- Radiation therapy: Used for many gliomas, especially higher-grade tumors or those that cannot be fully removed.
- Chemotherapy: Medicines, sometimes given with radiation, particularly for high-grade gliomas.
- Targeted therapy: Newer drugs aimed at specific gene changes in some gliomas.
- Supportive care: Medicines to control seizures and brain swelling, plus rehabilitation and symptom management.
Care is provided by a team that may include neurosurgeons, neuro-oncologists, and radiation specialists. The outlook ranges widely depending on the tumor.
Prevention
Most gliomas cannot be prevented because their cause is unknown. There is no proven way to avoid them through lifestyle. Sensible steps include:
- Avoiding unnecessary radiation exposure to the head
- Genetic counseling for families with inherited tumor syndromes
- Seeking prompt evaluation of persistent neurological symptoms so any tumor is found early
When to See a Doctor
See a doctor for new, persistent, or worsening headaches, changes in vision or thinking, or new weakness or numbness. Seek emergency care immediately for:
- A first-ever seizure
- Sudden severe headache, the worst of your life
- Sudden weakness, numbness, or trouble speaking
- Sudden vision loss or loss of consciousness
Frequently Asked Questions
Is a glioma always cancer?
Gliomas range from low-grade, slow-growing tumors to high-grade, aggressive ones. Even slower-growing gliomas need specialist care because they grow within the confined space of the brain or spine. The grade and type strongly affect treatment and outlook.
What is the most common symptom of a glioma?
Headaches and seizures are common early signs, along with weakness, numbness, or changes in speech, vision, or thinking, depending on the tumor's location. A first-ever seizure should be evaluated urgently.
What is glioblastoma?
Glioblastoma is a high-grade, aggressive type of glioma. It grows quickly and is treated with a combination of surgery, radiation, and chemotherapy, guided by a specialized care team.
How is a glioma diagnosed?
An MRI scan usually identifies the tumor, and a biopsy or surgery provides tissue to determine the exact type and grade. Molecular (genetic) testing of the tumor increasingly guides diagnosis and treatment.
When is a brain symptom an emergency?
Seek emergency care for a first-ever seizure, a sudden severe headache, sudden weakness or numbness, trouble speaking, or sudden vision loss, as these can also indicate a stroke or other urgent problem.
References
- National Cancer Institute (NCI). Adult Central Nervous System Tumors Treatment.
- Mayo Clinic. Glioma.
- MedlinePlus, U.S. National Library of Medicine. Brain tumor.
- National Institute of Neurological Disorders and Stroke (NINDS). Brain and Spinal Tumors.