A glioma is a tumor that develops in the brain or spinal cord and may result in headaches, seizures, and changes in cognition or personality. The condition can affect children or adults, where the glioma brain tumor may develop quickly or take several months to form. Most patients with glioma may get treated through a blend of therapies, including surgery, radiation therapy, and chemotherapy.
But what exactly is glioma, its causes, symptoms, and treatment methods? Read on to find out.
What is Glioma?
A glioma is a tumor that emanates from the glial cells that envelop and support the neurons of the CNS (Central Nervous System). These cells support nerves and help ensure the CNS functions optimally. However, when these cells grow out of control, they result in gliomas that usually grow in the brain or form within the spinal cord.
Typically, gliomas are cancerous (malignant) and can begin from the brain or spinal cord and spread within the CNS, but most patients have gliomas confined to the brain. In most cases, gliomas don’t spread but remain a life-threatening condition because of their ability to grow to other parts of the brain. Also, this form of cancer can be difficult to treat through surgery, especially in children.
Some of the common types of gliomas include;
- Astrocytomas: This type of glioma includes glioblastomas and diffuse intrinsic pontine gliomas because they often begin within the astrocytes. Astrocytomas and glioblastomas are aggressive forms that grow fast and are the most common malignant brain tumors among adults. Astrocytomas are common among children, often forming in the brain stem.
- Ependymomas: These tumors often begin in a type of glial cell called ependymocytes and develop in the ventricles of the spinal cord or brain. The cerebrospinal fluid can spread these tumors within the CNS, and it is more common in children than adults.
- Oligodendrogliomas: These tumors start in oligodendrocytes and often grow slowly, although they can become aggressive over time. They rarely spread outside the brain or spinal cord and are more common in adults than children.
What Causes Gliomas?
While doctors aren’t certain what causes glioma, the condition starts when glial cells in the spinal code or brain develop changes in the DNA. The DNA within the cell often tells it what to do, and it may tell it to make more cells. In such cases, the cells continue living while creating more healthy cells than dying, leading to several abnormal cells. This can result in a mass of cells called a tumor.
Gliomas develop due to the accumulation of mutations in selected genes, resulting in abnormal and uncontrolled growth. Studies report increased exposure to ionizing radiation and reduced risk with a history of allergies or atopic diseases that may cause gliomas. Some patients can develop gliomas by inheriting genetic mutations from their parents.
Common Symptoms of Gliomas
Like most brain tumors, symptoms of a glioma brain tumor often result due to increased pressure or irritation of the surrounding typical brain. As the tumor enlarges within the head, it can push outward on the developing skull, particularly for younger children. Some of the most common symptoms of gliomas include;
- Changes in mental status
- Neurological or personality deficits
- Nausea and vomiting
- Language impairment
- Confusion or a decrease in brain function, such as difficulty understanding information
- Vision problems such as double vision
During the diagnosis of glioma, your doctor checks for glioma symptoms and reviews your medical history. The healthcare provider will also perform a complete neurological and physical examination to determine the possibility of a tumor in your brain or spine. The diagnosis may also include MRIs and CT scans as imaging tools to look for tumors in the brain or elsewhere.
If your doctor sees any abnormal mass after imaging scans, they recommend a biopsy. A biopsy involves analyzing a sample of tissue to help determine if the tumor is cancerous or resulted due to an abnormal gene. The procedure also helps determine the grade of the tumor and the type of cells involved.
Glioma Treatment Options
Treatment options for gliomas often depend on various factors, including tumor type, grade, location, and size. Surgery is often the topmost course of treatment, followed by radiation and chemotherapy, mainly in high-grade gliomas.
The doctor may recommend observation if the tumor is small, benign, or in a high-risk region. However, surgery may come in handy to remove the tumor while avoiding to damage adjacent normal brain tissue. Surgery may be the best action for patients with low-grade gliomas as these tumors are less invasive. Surgery may not be suitable for aggressive gliomas due to the diffuse qualities of the tumor and its ability to infiltrate adjacent brain cells.
Radiation is often advisable after surgery, particularly for aggressive gliomas. Fractionated radiotherapy is the most popular radiation treatment, while intensity-modulated radiation therapy is a more advanced technique. For fractionated radiotherapy, patients have often been prescribed reduced doses of radiation over numerous visits. In contrast, intensity-modulated radiation therapy involves multiple beams of radiation aimed at the tumor in a 3D outline.
This treatment option involves drugs that destroy the tumor, often accompanied by radiation and surgery for aggressive gliomas. These include chemotherapeutic agents like temozolomide and bevacizumab that help reduce the progression rate of glioblastomas. Temozolomide is consumed as a pill to sensitize the tumor before radiation, while bevacizumab is best for recurring tumors and helps block the development of new blood vessels that sustain the tumor.
Other glioma treatment options include;
- Immunotherapy involves antibodies focused on the tumor cells carrying drugs, toxins, and radioactive compounds able to kill tumor cells.
- Gene therapy involves viral vectors that instantly deliver genes to cancerous cells, preventing tumor cell replication, killing cancerous cells, or promoting drug sensitivity.
- Vaccines comprising tumor cells increase the patient’s immune system’s response to kill tumor cells.
While glioma brain tumors originate from glial cells and the cause remains unknown, patients with this tumor can get diagnosed and treated. However, it is essential to understand various glioma symptoms to consult your doctors if you suspect you have gliomas. Besides, with surgery, radiation, and chemotherapy being the most recommended glioma treatment options, more treatment methods are on trial.