Oligodendroglioma

What is oligodendroglioma?

Oligodendroglioma is a type of brain tumor known as a glioma. This tumor gets its name from oligodendrocytes, cells that cover and protect nerves in the brain.

Oligodendrogliomas can occur most often in the white matter of the cerebrum. White matter is a network of pale-colored nerve fibers in the brain. White-matter cells transmit messages from one part of the brain to another. 

About half of all oligodendrogliomas are in the frontal lobe.

Most oligodendrogliomas occur in adults. They are rare in children and teens. These tumors make up less than 1% of brain tumors in children younger than 14.

Treatment usually includes surgery to remove as much of the tumor as possible. Radiation therapy is often used to kill remaining cancer cells. Chemotherapy may also be used.

Survival rates for children with oligodendroglioma depend on the tumor grade and success of surgery. Patients with low-grade tumors that are completely removed by surgery have a survival rate above 90%.

Your child’s care team is the best source of information about your child’s case.

Symptoms of oligodendroglioma

An oligodendroglioma often grows slowly. It may be present for years before it causes problems. Signs and symptoms of oligodendroglioma depend on the child’s age, tumor size and location, and how fast the tumor grows.

Oligodendroglioma symptoms may include:

• Seizures (most common)
• Changes in personality or behavior
• Headaches
• Vision problems
• Weakness or numbness on one side of the body

About half of patients experience seizures before diagnosis. Most patients (about 80%) will have seizures at some point during their illness.

Risk factors for oligodendroglioma

The cause of oligodendroglioma is unknown. But certain genetic changes in cells are linked to these tumors.

Oligodendrogliomas usually occur in adults. They are more common in males. Childhood oligodendrogliomas are most often seen in teens and young adults.

Diagnosis of oligodendroglioma

Doctors test for oligodendroglioma in several ways.

• A physical exam and medical history
• A neurological exam to check:
  • Memory
  • Vision
  • Hearing
  • Muscle strength
  • Balance
  • Coordination
  • Reflexes
• An electroencephalogram (EEG) to check electrical activity in the brain
• Imaging tests such as magnetic resonance imaging (MRI)
• A biopsy to check for abnormal cells

Staging of oligodendroglioma

Oligodendrogliomas are graded by how they look under the microscope. The more abnormal the cells look, the higher the grade. Oligodendrogliomas are usually grade 2 or 3.

• Grade 2 is considered low grade. The cells look like normal cells and grow slowly. Low-grade tumors are less likely to spread to other parts of the brain.
• Grade 3 is considered high grade. These tumors are called anaplastic oligodendrogliomas. They are more aggressive and can spread more easily.

Treatment of oligodendroglioma

Treatment of oligodendroglioma depends on:

• The type of tumor
• The tumor’s location
• Whether it has spread or come back

Aggressive tumors need more intensive treatment. Doctors also consider the patient’s age.

Radiation therapy is not used in young children because of the risk of side effects.

Follow-up care

After treatment, patients will have regular MRI scans to check for recurrence (if cancer has come back). Patients may need steroids and anti-seizure medicines for a time.

Prognosis for oligodendroglioma

Oligodendroglioma is much more common in adults than children. Less is known about the prognosis for young patients. Overall, children have better outcomes than adults.

The 5-year survival rate for childhood oligodendroglioma is greater than 80%. But treatment outcomes can vary widely based on the success of surgery, age at diagnosis, features of the tumor, and other factors. Recurrence is common, even among long-term survivors.

Outcomes vary based on:

• Type and grade of the tumor. Low-grade oligodendrogliomas grow slowly and are less likely to recur. High-grade tumors can be harder to treat and often recur sooner.
• Whether surgery can completely remove the tumor. Children with no visible tumor after surgery have the best chance of cure.
• Whether the cancer has spread. Cancer that has spread to other parts of the brain is harder to treat.
• Location of the tumor. Tumors in the cerebrum or cerebellum have a better chance of cure than tumors in the middle of the brain or brainstem. This is because they are easier to remove with surgery.
• Whether the cancer comes back. Recurrent disease is harder to treat.
  
• Molecular or genetic features of the tumor. Scientists are studying whether certain changes in genes and cells of the tumor can make the disease easier to treat with targeted therapy.

Every case is different. Your care provider can give you more information about your child’s case.

Support for patients with oligodendroglioma

Recovery and long-term effects of oligodendroglioma in children and teens depend on features of the tumor and treatments received. Your child will need ongoing follow-up care, lab tests, and routine MRI scans to monitor for recurrence or progression. Survivors of oligodendroglioma also should be monitored for late effects of therapy.

Your child’s care team will give you a survivorship care plan after treatment ends. This report includes needed tests and tips for a healthful lifestyle. Your care plan should also include referrals to support services such as neurology, rehabilitation therapy, school services, and psychology.

All cancer survivors should adopt healthy lifestyle habits. It is important to have regular medical checkups by a primary care physician.

Pediatric low-grade glioma as a long-term disease

Low-grade gliomas, including some oligodendrogliomas, are often a chronic or long-term disease. Although the long-term survival rate for low-grade glioma is high, the tumor often comes back or progresses over time.

Your child may need more treatments over many years of follow-up. This means the risk is higher for complications related to the tumor or treatment. There may also be times when the tumor shows growth on a scan, but the care team suggests observation instead of treatment.

Good communication and trust among your family, your child, and the care team are important.

More: Life After Brain Tumors

Questions to ask your care team

• What are our treatment options?
• What are the possible side effects of each treatment?
• What can be done to manage side effects?
• Will my child need to be in the hospital for treatment?
• Where is the treatment available? Is it close to home or will we have to travel?