Overview

Oligodendroglioma is a growth of cells that starts in the brain or spinal cord. The growth, called a tumor, begins in cells called oligodendrocytes. These cells make a substance that protects nerve cells and helps with the flow of electrical signals in the brain and spinal cord. Oligodendroglioma comes from cells that support the nerve cells, not the nerve cells themselves.

Oligodendroglioma usually forms in the brain. More rarely, it can form in the spinal cord. As the tumor grows, it can press on brain or spinal cord tissue and cause symptoms. Symptoms depend on which part of the brain or spinal cord is affected.

Oligodendrogliomas are rare. They are most common in adults, but they can happen at any age. Most of the time, this tumor grows slowly. Symptoms include seizures, headaches, and weakness or disability in a part of the body.

Treatment is with surgery, when possible. Sometimes surgery can't be done if the tumor is in a place that makes it hard to reach with surgical tools. Other treatments may be needed if the tumor can't be removed or if it's likely to come back after surgery. If you are diagnosed with oligodendroglioma, your healthcare team likely will monitor the tumor, even after treatment.

Symptoms

Oligodendrogliomas grow slowly, so symptoms may not occur for many years. Sometimes the condition is discovered when brain images are taken for another reason, such as severe headaches or a suspected concussion.

Seizures are usually the first symptom of oligodendroglioma. That's because these tumors often occur in the areas of the brain that support motor control. The brain tumor can disrupt the usual flow of the brain's electrical signals, which can cause a seizure.

Other symptoms of oligodendroglioma depend on the tumor size and location. They can include:

  • Changes in behavior.
  • Headaches.
  • Memory problems.
  • Numbness on one side of the body.
  • Problems speaking.
  • Problems thinking clearly.

When to see a doctor

If you notice ongoing symptoms that concern you, consider reaching out to a healthcare professional, clinic or trusted community health resource for advice.

Causes

The cause of oligodendroglioma often isn't known. This tumor starts as a growth of cells in the brain or, more rarely, in the spinal cord. It forms in cells called oligodendrocytes. They protect nerve cells and help with the flow of electrical signals in the brain.

Oligodendroglioma happens when oligodendrocytes develop changes in their DNA. A cell's DNA holds the instructions that tell the cell what to do. In healthy cells, the DNA gives instructions to grow and multiply at a set rate. The instructions tell the cells to die at a set time.

In tumor cells, the DNA changes give different instructions. The changes tell the tumor cells to grow and multiply quickly. Tumor cells can keep living when healthy cells would die. This causes too many cells.

To diagnose oligodendroglioma, healthcare professionals look for DNA changes called IDH mutations. They also look for specific changes in the chromosomes of the tumor cells. The medical description for this type of tumor is oligodendroglioma, IDH-mutant, 1p/19q-codeleted.

The tumor cells form a growth that may press on nearby parts of the brain or spinal cord as the growth gets bigger. Sometimes the DNA changes turn the tumor cells into cancer cells. Cancer cells can invade and destroy healthy body tissue.

Risk factors

Risk factors for oligodendroglioma include:

  • History of radiation exposure. A history of radiation to the head and neck can increase a person's risk.
  • Adult age. This tumor can happen at any age. But it's more often found in adults in their 40s and 50s.
  • White race. Oligodendroglioma happens most often in white people who don't have Hispanic ancestry.

There is no way to prevent oligodendroglioma.

Oct. 08, 2025

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