Glioblastoma Multiforme (GBM)

MSK radiation oncologist and glioblastoma multiforme (GBM) expert Kathryn Beal with a patient

MSK radiation oncologist Kathryn Beal is part of a team of experts devoted to providing compassionate care for people with glioblastoma multiforme (GBM).

If you or someone you love has been diagnosed with glioblastoma, you may have questions about available treatment options and prognosis. We’re here to help. Learning as much as you can about the disease can help you feel better prepared to speak with doctors about your condition and possible treatment. At Memorial Sloan Kettering, a world-class team of experts is dedicated to giving you the best medical outcome and quality of life possible.

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About Glioblastoma

Glioblastoma: Grade IV Tumor

Glioblastoma is considered a grade IV tumor, the most aggressive type. Glioblastoma is not categorized by stages, as cancers usually are.

Glioblastoma, also called glioblastoma multiforme or GBM, is a type of primary brain cancer. It arises in brain cells called astrocytes, a type of supportive (glial) cell that makes up the connecting tissue of the brain. Glioblastoma is a fast-growing cancer that can spread quickly throughout the brain. It does not usually spread to other areas of the body. Doctors classify brain tumors from grade I to grade IV based on their aggressiveness. Glioblastoma is considered a grade IV tumor, the most aggressive type. (Glioblastoma is not categorized by stages, as cancers usually are.)

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Glioblastoma Symptoms

Symptoms of glioblastoma are related to pressure in the brain and may include:

  • headache
  • nausea
  • vomiting
  • drowsiness
  • personality or mood changes
  • speech difficulties
  • eyesight changes

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Glioblastoma Treatment

Glioblastoma tumors are challenging to remove completely with surgery. For that reason, they are difficult to cure. However, new approaches and clinical trials are showing promise at delaying when the disease comes back and extending survival.

Our team of radiation oncologists, neurosurgeons, neuro-radiologists, neuro-pathologists, neuro-oncologists, and medical physicists at Memorial Sloan Kettering have unparalleled experience in treating glioblastoma. We meet regularly to review and discuss the best care plan for each patient. The goals of treatment are to help ease patients’ symptoms and to slow or stop the growth of glioblastoma tumors.

Our treatment approaches include:

  • MRI-guided microneurosurgery
  • stereotactic radiosurgery
  • image-guided radiation or re-irradiation
  • proton therapy
  • chemotherapy
  • immunotherapy
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Glioblastoma Experts

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Glioblastoma Surgery

Surgery is usually the first treatment for glioblastoma. The goals of surgery are to relieve pressure in the brain and to safely remove as much of the tumor as possible. This is done before giving other treatments, such as radiation or chemotherapy.

Glioblastoma tumors typically are found in one of the two halves of the outermost region of the brain, but they can occur anywhere in the brain or spinal cord. These tumors can be hard to remove completely because they tend to have irregular patterns of growth and a complex shape. They may also have microscopic extensions that can work their way into vital parts of the brain, such as the regions controlling speech and motor coordination.

At MSK, we use a range of sophisticated imaging techniques, including functional MRI, to help see the shape and location of tumors before surgery. This imaging can be combined with a computerized view of the brain to help surgeons determine how much of the tumor is accessible and whether there are risks to brain function from performing surgery.

MSK neurosurgeons have vast experience with glioblastoma. They have access to the most advanced imaging equipment, state-of-the-art surgical microscopes, and even an MRI scanner right in the operating room to evaluate on the spot whether more of the tumor can be removed safely. Postoperative care at MSK, provided by our expert nursing staff, is second to none. Our nurses received Magnet® recognition in 2016 for their outstanding performance in delivering patient-centered care.

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Radiation for Glioblastoma

Radiation therapy is part of the treatment for glioblastoma and typically occurs following surgery. Radiation may be used as the sole treatment when a glioblastoma tumor is located in an area that is not appropriate for surgery. Studies have shown that people live longer when given the combination of surgery and radiation therapy compared with surgery alone.

Radiation is usually given along with a chemotherapy drug called temozolomide (Temodar) that makes the tumor more sensitive to the radiation. Studies have shown this combination to be more effective than radiation without temozolomide.

Radiation can be directed precisely to the tumor, sparing the nearby healthy tissues and leading to better outcomes for patients. We are able to verify within millimeters that the setup for each patient is accurate and can be reproduced from treatment to treatment.

The most common schedule of radiation therapy is daily treatment with a low dose of radiation delivered over six weeks. This amount of radiation is well tolerated by most patients, causing few side effects.

The most common form of radiation delivery is external-beam radiation, in which treatment is delivered from a machine called a linear accelerator. External-beam radiation can be delivered from different angles in higher doses with intensity-modulated radiation therapy (IMRT).

On occasion, we also use proton therapy, another form of external-beam radiation. This is most frequently used for glioblastoma tumors that are deep in the brain, or occasionally for re-treatment. When we recommend treatment with proton therapy, we use a facility in New Jersey that has a special machine called a cyclotron to produce protons. We are also building a proton facility in northern Manhattan, expected to open in 2018.

Brain Tumor Center
Memorial Sloan Kettering’s Brain Tumor Center brings together scientists and clinicians with the goal of developing truly effective brain tumor therapies.
Learn more
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Chemotherapy for Glioblastoma

The chemotherapy drug temozolomide is usually given along with radiation to treat glioblastoma. This drug sensitizes the tumor to the radiation, making the latter more effective. Temozolomide is also continued for a minimum of six months after completion of radiotherapy.

The targeted drug bevacizumab (Avastin) is sometimes used to treat glioblastoma. This drug works by blocking the growth of new blood vessels that nourish the tumor. Bevacizumab is usually used once the tumor returns and can be very effective at easing symptoms. It is rarely used as part of the initial therapy.

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Glioblastoma Immunotherapy

Immunotherapy is any treatment that uses the immune system to fight cancer. While no immunotherapies are yet approved by the FDA for the treatment of glioblastoma, several early-stage clinical trials have suggested that immunotherapies might be effective in treating the disease. Doctors at MSK are actively pursuing immunotherapy approaches for treating glioblastoma.

Checkpoint inhibitors

Drugs called checkpoint inhibitors, including pembrolizumab (Keytruda) and nivolumab (Opdivo), are being tested in glioblastoma. These drugs work by “releasing the brakes” on the immune system, empowering it to go after and fight cancer.


Another immunotherapy approach that is being tested is therapeutic cancer vaccines. These therapies work by presenting the body with fragments of proteins called antigens that the immune system recognizes as foreign and dangerous. Glioblastoma cells make a number of antigens that are unique to the cancer cells, which makes them attractive targets.

Sometimes, genetically modified viruses are used to kill cancer cells and release cancer-specific antigens.

Cell-based therapies

Chimeric antigen receptor (CAR) T therapies, which give new information to immune cells so they recognize cancer cells as foreign, are also being explored as a treatment for glioblastoma.

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Glioblastoma Research and Clinical Trials

Even with surgery, radiation, and drug-based therapies, glioblastoma tumors are unlikely to be cured. The disease usually comes back and is fatal.

At MSK, we are constantly working to improve our treatment strategy and extend survival for people with gliobastoma. This includes making advances in precision surgery and radiation therapy, as well as developing new drug therapies.

Glioblastoma tumors tend to vary on the cellular and molecular level, which means that a treatment that works against some cells might not work against others. Our scientists are making progress in understanding genetic subtypes of glioblastoma. This research is enabling better classification of tumors according to their underlying biology. The ultimate goal is to create focused drugs that can target specific mutations.

At MSK we utilize precision medicine in our treatment of glioblastoma. All MSK patients have access to a test called MSK-IMPACT™, which can determine if a person’s glioblastoma has certain genetic mutations that make them eligible for targeted therapies that are commercially available or available through clinical trials. We have seen dramatic responses to drugs that attack a unique genetic vulnerability in an individual’s tumor. We use MSK-IMPACT to identify any mutations in patients’ tumors so that we can most accurately tailor their therapy.

Nearly every treatment that is available to patients today exists because of a clinical trial. MSK currently has several open clinical trials testing new drugs and therapies for people with glioblastoma. In addition to our main location in Manhattan, we have neuro-oncologists at every MSK regional site where we also offer our clinical trials.

For a list of available clinical trials for glioblastoma, visit our clinical trial finder.

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