Glioma

Glioma is a common type of brain tumor that starts in glial cells, which support nerve cells in the brain and spinal cord. These tumors can be non-cancerous (benign) or cancerous (malignant). Symptoms vary based on the tumor's size and location, often including headaches, seizures, or changes in personality.

What is Glioma?

Glioma is a type of tumor that begins in the brain or spinal cord, specifically in cells called glial cells. These cells normally surround and support nerve cells. Gliomas are the most common kind of primary brain tumor and can range from slow-growing (benign) to aggressive (malignant) forms.

Gliomas develop from glial cells, which are essential support cells for the brain and spinal cord. These cells help protect and nourish neurons (nerve cells). When glial cells grow abnormally, they can form a tumor. There are several types of gliomas, named after the specific glial cell they originate from. Common types include astrocytomas, oligodendrogliomas, and ependymomas. The most aggressive and common type of glioma is called a glioblastoma. While gliomas can grow and spread within the brain or spinal cord, they rarely spread to other parts of the body. The behavior of a glioma, including how fast it grows, depends on its specific type and grade.

Symptoms

Glioma symptoms depend on the tumor's size, location, and growth rate within the brain or spinal cord. Common signs include new or worsening headaches, seizures, nausea, vomiting, and changes in personality or memory. These symptoms occur as the tumor presses on or damages nearby brain tissue.

Headaches are a frequent symptom, often described as new, persistent, or worse than usual. They may be more severe in the morning and sometimes improve after vomiting. Seizures, which are sudden bursts of uncontrolled electrical activity in the brain, can also occur. Other symptoms can include nausea and vomiting, which may not be related to food. You might notice changes in your personality, mood, or memory, or experience confusion. Some people develop weakness or numbness in their arms or legs. Vision problems, such as blurred vision, double vision, or loss of peripheral (side) vision, can also be signs. Difficulties with speech, such as slurring words or finding the right words, and problems with balance or coordination are also possible. These symptoms often develop gradually over time.

Causes & risk factors

The exact cause of most gliomas is not fully understood, but certain factors can increase your risk. These include increasing age, previous exposure to radiation, and, rarely, a family history of specific genetic conditions. Most people with gliomas do not have clear risk factors.

For most people, the reason a glioma develops is unknown. Scientists continue to study what might cause these tumors to form. It is important to remember that having a risk factor does not mean you will definitely get a glioma, and many people with gliomas have no known risk factors. One risk factor is age; the risk of developing a glioma generally increases as you get older. Another rare risk factor is exposure to high doses of radiation, such as radiation therapy received for a previous cancer. A very small number of gliomas are linked to inherited genetic conditions that run in families. Examples include neurofibromatosis type 1, Li-Fraumeni syndrome, and tuberous sclerosis. If you have a family history of these conditions, discuss it with your doctor.

How it's diagnosed

Diagnosing a glioma typically begins with a neurological exam to check your brain and nerve function. Imaging tests like magnetic resonance imaging (MRI) are then used to locate the tumor. A biopsy, which involves taking a tissue sample for examination, is usually needed to confirm the diagnosis and determine the tumor type.

Your doctor will first perform a neurological exam. During this exam, they will check your vision, hearing, balance, coordination, strength, and reflexes. This helps them identify which parts of your brain might be affected by a tumor. Imaging tests are crucial for seeing the tumor. An MRI (magnetic resonance imaging) scan is the most common and detailed imaging test used. A CT (computed tomography) scan or a PET (positron emission tomography) scan may also be used to provide more information about the tumor's size and location. To confirm a glioma diagnosis, doctors usually need a biopsy. This procedure involves surgically removing a small piece of the tumor tissue. A specialist then examines this tissue under a microscope to determine the exact type and grade of the glioma. Molecular testing of the tumor tissue can also provide important information for treatment planning.

Treatment options

Glioma treatment options depend on the tumor's type, size, location, and your overall health. Common treatments include surgery to remove as much of the tumor as possible, radiation therapy to kill cancer cells, and chemotherapy. Targeted drug therapy and other specialized treatments may also be used.

The primary goal of treatment is often to remove as much of the tumor as safely possible through surgery. Even if the entire tumor cannot be removed, surgery can help reduce symptoms and improve the effectiveness of other treatments. Radiation therapy uses high-energy beams, such as X-rays or protons, to destroy tumor cells or slow their growth. This treatment is often used after surgery or as a primary treatment if surgery is not possible. Chemotherapy involves using drugs, taken orally or injected, to kill cancer cells throughout the body. Other treatments may include targeted drug therapy, which focuses on specific abnormalities within cancer cells. Tumor Treating Fields (TTF) therapy uses electric fields to disrupt the growth of cancer cells. Rehabilitation, including physical, occupational, and speech therapy, is also an important part of recovery to help manage symptoms and improve function. Your care team may also discuss clinical trials, which offer access to new and experimental treatments.

Recovery & outlook

The recovery and outlook for someone with a glioma vary significantly. They depend on factors like the tumor's type and grade, its location, how much of it could be removed, your age, and overall health. Some gliomas are slow-growing, while others, like glioblastoma, are very aggressive and have a poorer prognosis.

Recovery from glioma treatment can be a long process. It often involves managing side effects from surgery, radiation, or chemotherapy. Many people benefit from rehabilitation services, such as physical therapy to regain strength, occupational therapy to help with daily tasks, and speech therapy for communication difficulties. The outlook, or prognosis, for a glioma is highly individual. Low-grade gliomas tend to grow slowly and may allow for a longer survival time. High-grade gliomas, especially glioblastoma, are more aggressive and challenging to treat, leading to a shorter life expectancy. Your medical team will discuss your specific prognosis based on the characteristics of your tumor and your response to treatment. It is important to have open conversations with your doctors about what to expect and to seek support from family, friends, and support groups.

When to see a doctor

You should see a doctor if you experience new, persistent, or concerning symptoms that might suggest a glioma. These include headaches that are worsening or unusual, unexplained seizures, sudden changes in vision or speech, or new weakness or numbness in your body. Early evaluation is important for any neurological changes.

It is important to pay attention to your body and seek medical advice if you notice any unusual or persistent changes. While many symptoms can be caused by less serious conditions, it is always best to have them checked by a healthcare professional. Specifically, you should contact your doctor if you develop headaches that are new, severe, or do not go away, especially if they are worse in the morning or accompanied by nausea and vomiting. Any new seizure activity, even a brief one, warrants immediate medical attention. Other red-flag symptoms include unexplained changes in your vision, such as blurriness or double vision, or difficulty speaking or understanding others. If you experience new weakness, numbness, or problems with balance and coordination, or if family members notice significant changes in your personality or memory, you should also consult a doctor promptly.

Frequently asked questions

Can gliomas spread to other parts of the body outside the brain?

Gliomas rarely spread beyond the brain or spinal cord to other parts of the body. They typically grow and spread within the central nervous system.

Are all gliomas cancerous?

No, not all gliomas are cancerous. Some gliomas are benign (non-cancerous) and grow slowly, while others are malignant (cancerous) and can be very aggressive, like glioblastoma.

Is there a genetic test to see if I will get a glioma?

While a very small number of gliomas are linked to rare inherited genetic syndromes, there isn't a general genetic test to predict if most people will get a glioma. Most cases are not tied to a family history.

How quickly do gliomas grow?

The growth rate of a glioma varies greatly depending on its type and grade. Some low-grade gliomas can grow very slowly over many years, while high-grade gliomas, such as glioblastoma, can grow rapidly.

What is the difference between an astrocytoma and a glioblastoma?

Both astrocytomas and glioblastomas are types of gliomas that start in astrocyte cells. Glioblastoma is considered the most common and most aggressive type of astrocytoma, classified as a high-grade tumor.

Can lifestyle changes prevent gliomas?

Currently, there is no clear evidence that specific lifestyle changes can prevent gliomas. The causes for most gliomas are unknown, and known risk factors like age or rare genetic conditions are not typically influenced by lifestyle.

Sources

• MedlinePlus — Glioma
• Mayo Clinic — Glioma
• Cochrane Library — Glioma