Glioblastoma Awareness Day: Understanding an Aggressive Brain Cancer

A day set by resolution

Glioblastoma Awareness Day falls on the third Wednesday of July. The Senate marks it by resolution each year: July 16 in 2025, July 15 in 2026.

The 2025 resolution, S.Res. 285, is worth reading, because a Senate preamble is an unusual place to find plain numbers about a disease. It states that glioblastoma is the most common malignant brain tumor, making up roughly half of all primary malignant brain tumors, and that more than 13,000 people in the United States were expected to be diagnosed in 2025.

It also states that the five-year survival rate is 6.9 percent and that median survival is about 8 months. And it notes that only 5 drugs and 1 device have been approved by the FDA specifically for glioblastoma since the disease was first described in the 1920s.

What the tumor is

Glioblastoma is a primary brain tumor, meaning it starts in the brain rather than spreading there from somewhere else. It is a glioma, arising from the supporting cells of the brain rather than from neurons.

NCI's summary for clinicians groups glioblastomas with anaplastic astrocytomas as the largest category of primary brain tumors, at 38 percent. Meningiomas and related tumors come next at 27 percent.

Primary brain tumors rarely spread to the rest of the body. They spread within the brain and along the spinal axis instead. That difference shapes everything about how the disease is treated. Our page on glioblastoma covers it in more depth.

Why the biopsy report matters so much

The Senate resolution notes that in 2021 the definition of glioblastoma changed, so that biomarker testing became essential for anyone suspected of having one. NCI's summary explains why.

Three genetic features now carry real weight in diffuse gliomas.

Methylation of the MGMT gene promoter. MGMT is a DNA repair enzyme. When its promoter is switched off by methylation, the tumor repairs itself less well, and chemotherapy works better. In the trial that set the standard of care, median overall survival was 18.2 months with MGMT methylation and 12.2 months without.

Variants in the IDH1 or IDH2 genes. These separate tumors that look similar under a microscope but behave differently.

Codeletion of chromosomes 1p and 19q, which marks a distinct group of gliomas.

Our page on brain tumor grades and diagnosis explains how these results are reported.

What treatment involves

NCI states that the standard treatment for newly diagnosed glioblastoma is surgery, followed by radiation given at the same time as daily temozolomide, then six further cycles of temozolomide.

The numbers behind that come from a trial run by the EORTC and the National Cancer Institute of Canada in 573 people. Radiation was 60 Gy given in 2 Gy fractions over 6 weeks. Adding temozolomide gave a hazard ratio for death of 0.6. Three-year overall survival was 16.0 percent with the combination, against 4.4 percent with radiation alone.

Several things that were tried did not help. Giving temozolomide on a longer, denser schedule did not improve survival, at any MGMT status. Adding bevacizumab to standard treatment did not improve overall survival in either of two large randomized trials, though it did lengthen the time before the disease progressed.

For disease that comes back, NCI notes that bevacizumab alone became standard therapy after an accelerated FDA approval in 2009, based on response rates rather than survival.

When to get checked

There is no screening test for glioblastoma. The Senate resolution says so directly: there are no screening or early detection methods.

That makes symptoms the only route in. NCI lists the general signs of a brain tumor:

• Headaches.
• Seizures.
• Changes in vision.
• Loss of appetite, nausea and vomiting.
• Changes in personality, mood, mental capacity or concentration.

Two of those deserve emphasis. A first seizure in an adult with no history of epilepsy always needs investigation. NCI notes that seizures are the presenting symptom in about 20 percent of people with tumors in the upper part of the brain. Our page on seizures and brain tumors covers what that assessment involves.

The other is personality change. It is often noticed first by family rather than by the person, and it is easy to attribute to stress or age. It belongs in the same category as the rest of the list.

Most headaches are not tumors. A headache that is new, different from your usual pattern, worse in the morning, or comes with vomiting or new neurological symptoms is the kind worth an appointment. Our page on brain tumor symptoms goes through each one.

The group picture

SEER figures cover brain and other nervous system cancers together, which is a wider group than glioblastoma alone.

Five-year relative survival across that group is 32.9 percent for cases from 2016 to 2022. An estimated 24,740 new cases and 18,350 deaths are projected for 2026, and the median age at diagnosis is 61.

Glioblastoma sits far below that group average. The Senate resolution's figure of 6.9 percent at five years is the one that describes this specific tumor.

What this does not mean

A median of 8 months is a middle point across a large group of people. Half were above it. It is not a countdown, and it does not describe any individual.

Nor is it fixed by biology alone. Age, how much of the tumor can be safely removed, how well a person is functioning at diagnosis, and MGMT status all shift the picture.

The resolution names one more thing worth carrying: relative to other cancers, brain cancer patients pay the second highest out-of-pocket costs for medical services, both at the start of care and at the end. That is not a medical fact about the tumor. It is a fact about what having it costs.

Sources

• U.S. Senate, S.Res. 285 (119th Congress), Designating July 16, 2025, as Glioblastoma Awareness Day — https://www.govinfo.gov/content/pkg/BILLS-119sres285ats/pdf/BILLS-119sres285ats.pdf
• U.S. Senate, S.Res. 786 (119th Congress), Designating July 15, 2026, as Glioblastoma Awareness Day — https://www.govinfo.gov/content/pkg/BILLS-119sres786ats/pdf/BILLS-119sres786ats.pdf
• NCI PDQ, Adult Central Nervous System Tumors Treatment (Health Professional Version) — https://www.cancer.gov/types/brain/hp/adult-brain-treatment-pdq
• NCI, Brain Tumors — https://www.cancer.gov/types/brain
• SEER Cancer Stat Facts, Brain and Other Nervous System Cancer — https://seer.cancer.gov/statfacts/html/brain.html

How this article was prepared

An AI-assisted editorial system helped prepare this page. No named medical reviewer has reviewed it unless one is listed.

The National Cancer Information Foundation publishes Cancer Explained. This page is for learning. It is not medical advice and does not suggest a test or treatment.

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