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Glioblastoma multiforme

Medically reviewed by Last updated on Jun 24, 2023.

What is Glioblastoma multiforme?

Harvard Health Publishing

Glioblastoma multiforme is a fast-growing brain or spinal cord tumor. It affects the brain more often than the spinal cord. These tumors grow from glial cells which form the (supportive) tissue of the brain and spinal cord. Glioblastoma multiforme is also called glioblastoma, grade IV astrocytoma, or GBM.

As it grows, a brain tumor can press against or damage nerves or other structures. This can interfere with the brain's normal functioning. For example, a brain tumor can disrupt

Scientists do not know what causes most brain tumors. However, they are working to better understand the biology of glioblastoma multiforme and identify possible environmental, occupational, family, and genetic risk factors.


As brain tumors grow, they press against or damage nerves or other parts of the brain and interfere with thought, memory, emotion, movement, vision, hearing, touch, and other brain functions. Swelling and fluid buildup can also affect brain function.

The most common symptoms of glioblastoma are

Many other conditions can cause these symptoms, but call your doctor promptly if you experience any of these problems.


Diagnosis often begins with a medical history. Your doctor will ask you about your symptoms and past illnesses and treatments.

Your doctor will also do a neurological examination—she or he will check your

He or she may check your eyes for signs of increased pressure or swelling.

Your doctor may also order one of the following imaging tests:

The only way to be sure that a brain tumor is a glioblastoma is by looking directly at the tumor tissue. Your doctor takes a sample of the tumor, which is then examined under the microscope.

Patients with glioblastoma often work with several types of doctors. These specialists include

Expected duration

A brain tumor will continue growing until it is treated. Without treatment, permanent brain damage or death can result.


There is no known way to prevent glioblastoma. Some risk factors may increase a person's chance of developing a brain tumor. These include radiation therapy to the brain and certain inherited disorders.


The treatment of glioblastoma usually requires surgery followed by additional cancer therapies. Treatment aims to

Treatment depends on the patient's medical and personal situations. It generally includes surgery, radiation, and chemotherapy.

Surgery. In most cases, surgery is the first step in treatment. The goal is to remove as much of the tumor as possible. This helps to relieve symptoms. Doctors can also examine the tumor tissue to confirm the glioblastoma diagnosis.

Sometimes a biopsy is done instead of surgery to confirm the diagnosis. This might be done if a patient is not healthy enough to withstand surgery.

Glioblastoma tumors grow like tentacles into surrounding brain tissue, so it is often not possible to remove them completely. That's why the treatment plan usually includes additional therapy to destroy the remaining cancer cells.

Radiation. Radiation therapy uses high-energy x-ray beams to stop or slow tumor growth. Patients usually get radiation treatment following biopsy or surgery.

External beam radiation therapy aims high-powered x-rays at the tumor and surrounding tissues from outside the body. Another approach is called interstitial radiation or brachytherapy. In this case, radioactive substances are implanted directly into a tumor.

Proton therapy is a type of radiation often used for patients with glioblastoma. Proton therapy provides pinpoint focusing of the radiation beam to the tumor. This lessens the chance of damage to surrounding normal brain tissue.

Chemotherapy. Chemotherapy uses drugs to stop the growth of cancer cells. It can be taken by mouth, or injected into a vein or muscle.

Some chemotherapy drugs destroy cancerous cells or prevent them from reproducing. Others alter a tumor's behavior by changing the environment around it.

Several medicines are available to help manage the symptoms of glioblastoma. These drugs can reduce swelling around the tumor, control seizures, and lessen nausea and vomiting.

Treatment options

The following list of medications are related to or used in the treatment of this condition.

View more treatment options

When to call a professional

Contact your doctor if you experience any of the common symptoms of glioblastoma, including:


Glioblastoma tumors are among the most malignant. Younger patients tend to have better outcomes. Sadly, only a small percentage of adults survive five years beyond their diagnosis.

Additional info

National Cancer Institute (NCI)

American Cancer Society (ACS)

National Brain Tumor Society

Dana-Farber Cancer Institute

Learn more about Glioblastoma multiforme

Treatment options

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.