What are the types of gliomas?

The type of glioma is based on the kind of cells where they first start to grow. 

Astrocytoma (AS-troh-sy-TOH-muh) tumors start in the glial cells called astrocytes. The most aggressive astrocytoma is a glioblastoma. Other names for glioblastoma are GBM or glioblastoma multiforme.

• Diffuse intrinsic pontine glioma (dih-FYOOS in-TRIN-sik PON-teen glee-OH-muh), known as DIPG and diffuse midline gliomas (DMGs). These are astrocytomas that spread along fiber tracts. The thalamus and cerebellum are the most common sites. DIPGs are a very aggressive type of DMG and are hard to treat.

When we diagnose an astrocytoma or a diffuse glioma, we check for a change (mutation) in a gene called isocitrate dehydrogenase (IDH). This mutation is found in most low-grade diffuse gliomas.

If we find an IDH mutation, we may prescribe vorasidenib. In 2024, the U.S. Food and Drug Administration approved vorasidenib for low-grade diffuse gliomas with an IDH gene mutation. 

Oligodendroglioma (AH-lih-goh-DEN-droh-glee-OH-muh) starts in the glial cells called oligodendrocytes.  These cells cover and protect nerve cells in the brain and spinal cord. This is kind of glioma grows slowly and is less common.

Oligodendrogliomas have an IDH mutation. MSK is studying new treatments for tumors, including oligodendrogliomas, that have this mutation.

Brain stem glioma is a tumor that starts in the part of the brain that connects to the spinal cord (the brain stem). It can grow fast or slowly. 

Ependymoma (eh-PEN-dih-MOH-muh) starts in ependymal cells. These cells line the hollow ventricles (cavities) in the brain and the central canal of the spinal cord. This is a rare kind of glioma.

What are the grades of a glioma?

Each of these types can be broken into grades 1 through 4. Treatment depends on the glioma’s type and grade. The lower the number, the more slowly the glioma grows.  

Grades 1 and 2 are low-grade gliomas. Low-grade gliomas can still be a very serious kind of cancer.  Although they grow slowly, they can grow into a healthy brain. This can cause symptoms, or even death. 

Low-grade gliomas can become high grade (grades 3 and 4).