Diffuse Midline Glioma Overview
Diffuse midline glioma is a rare type of primary central nervous system (CNS) tumor that originates in the midline structures of the brain, which include the pons in the brainstem, the thalamus, the spinal cord and the cerebellum. More specifically, the tumor arises in glial cells, which support the function of nerve cells (neurons). Characterized by an infiltrative growth pattern, the cancer tends to be aggressive. Although it is most commonly diagnosed in pediatric patients, diffuse midline glioma can occur in individuals of any age.
Diffuse midline glioma causes
Like most types of cancer, diffuse midline glioma is caused by harmful changes to the genes that control cellular function (DNA). As a result of the changes, the cells grow and divide uncontrollably, eventually forming a tumor. The precise triggers of the cellular DNA mutations that lead to the development of diffuse midline glioma are unknown.
Diffuse midline glioma risk factors
Researchers have determined that some people are at heightened risk of developing diffuse midline glioma due to a genetic condition, such as:
- Li-Fraumeni syndrome
- Neurofibromatosis type 1 (NF1)
- h3K27M mutation
Diffuse midline glioma symptoms
The warning signs of diffuse midline glioma can vary based on the location of the tumor. Some common symptoms include:
- Blurred or double vision
- Difficulty swallowing
- Weakness on one or both sides of the body
- Loss of balance
Diffuse midline glioma in the brain may also increase the production of cerebrospinal fluid (CSF) or block its normal flow, both of which can lead to fluid buildup in deep brain cavities and increase pressure within the skull. Known as hydrocephalus, this condition can cause:
- Nausea and vomiting
- Irritability
- Headaches
- A strong desire to sleep
- Seizures
Diffuse midline glioma in the spine can cause:
- Progressive weakness
- Numbness
- Loss of bladder or bowel control
Diffuse midline glioma diagnostic testing
In magnetic resonance imaging (MRI) scans, diffuse midline glioma often looks like a mass that has spread throughout the midsection of the brain. Because the tumor may resemble glioblastoma and other high-grade brain cancers, a biopsy is needed to confirm the diagnosis.
Diffuse midline glioma treatment
When possible, diffuse midline glioma treatment usually begins with surgery. The goal is two-fold: First, the surgeon will obtain a sample of tumor tissue for microscopic analysis by a pathologist, who can confirm the diagnosis and determine the tumor type, an important consideration for planning further treatment. Second, the surgeon will remove as much of the cancer as possible while minimizing any disruption to the surrounding healthy structures. If the tumor has caused hydrocephalus, a ventriculoperitoneal shunt may be placed to redirect the flow of CSF.
In most cases, surgery is followed by radiation therapy. If the risk of surgical biopsy is determined to be too high, diffuse midline glioma may be treated with radiation therapy alone or in combination with chemotherapy. Some patients choose to participate in brain cancer clinical trials, where they can benefit from promising new chemotherapy, targeted therapy or immunotherapy drugs before those options are made available elsewhere.
Benefit from world-class care at Moffitt Cancer Center
At Moffitt, the multispecialty team in our Neuro-Oncology Program includes highly respected neurosurgeons, neuro-oncologists, neuroradiologists, radiation oncologists and other specialists. Working together, we develop an individualized treatment plan for each patient to ensure the best possible outcome and quality of life. Complex diffuse midline glioma cases are also reviewed by our brain tumor board.
If you have questions about diffuse midline glioma, you can request an appointment with a specialist in our Neuro-Oncology Program by calling 1-888-663-3488 or submitting a new patient registration form online. We do not require referrals.