Glioblastoma is rare, yet it is relentless, and in the US the age adjusted incidence rate from 2015 to 2019 was 3.19 per 100,000 person years. What stands out is how the disease presents and evolves differently from person to person, from headache in 50 to 60% of patients and seizures at diagnosis in 30 to 50%, to survival that averages only 15 months under standard therapy. Let’s look at the clinical, molecular, and outcome figures side by side to see where the patterns tighten and where they break.
Key Takeaways
- Headache is the most common initial symptom in 50-60% of glioblastoma patients
- Seizures occur at presentation in 30-50% of glioblastoma cases
- Cognitive impairment is reported in 40% of newly diagnosed glioblastoma patients
- The age-adjusted incidence rate of glioblastoma in the United States from 2015-2019 was 3.19 per 100,000 person-years
- Glioblastoma accounts for 14.3% of all primary brain tumors and 48.6% of all malignant primary brain tumors in the US (CBTRUS 2021)
- The median age at diagnosis for glioblastoma is 65 years, with 75% of cases occurring in individuals over 55 years old
- Glioblastoma is characterized by pseudopalisading necrosis in 90% of cases
- IDH1/2 wild-type status is present in 90-95% of primary glioblastomas
- EGFR amplification occurs in 40-60% of glioblastoma tumors
- Median OS with standard therapy is 15 months, dropping to 9 months with age >60
- 5-year survival rate for glioblastoma is 6.9% overall (SEER 2015-2019)
- IDH-mutant glioblastomas have 27-month median OS vs 14 months wild-type
- Maximal safe resection is achieved in 30-40% of glioblastoma cases
- Standard treatment includes temozolomide (TMZ) with radiotherapy yielding median OS of 14.6 months (Stupp protocol)
- Gross total resection improves survival by 3-5 months compared to biopsy only
Glioblastoma incidence is highest in older adults, and despite treatment, median survival is about 15 months.
Related reading
01 · Category
Clinical Presentation28 stats
01
Headache is the most common initial symptom in 50-60% of glioblastoma patients
02
Seizures occur at presentation in 30-50% of glioblastoma cases
03
Cognitive impairment is reported in 40% of newly diagnosed glioblastoma patients
04
Hemiparesis develops in 25-35% of patients prior to diagnosis
05
Nausea and vomiting due to increased intracranial pressure in 25% of cases
06
Aphasia presents in 20-30% of left temporal lobe glioblastomas
07
Visual field defects occur in 15% of glioblastoma patients at onset
08
Personality changes noted in 10-20% of frontal lobe glioblastomas
09
Ataxia is a symptom in 10% of cerebellar-infiltrating glioblastomas
10
Cranial nerve palsies appear in 5-10% of brainstem-proximal glioblastomas
11
Mean symptom duration before diagnosis is 3-6 months
12
70% of glioblastomas are supratentorial, leading to focal deficits
13
Memory loss affects 25% of temporal lobe glioblastoma patients
14
Dysphasia incidence is 35% in dominant hemisphere tumors
15
Fatigue is reported by 60% of glioblastoma patients at presentation
16
Sensory disturbances in 15% of parietal lobe glioblastomas
17
Hydrocephalus symptoms in 20% due to ventricular obstruction
18
Diplopia from sixth nerve palsy in 8% of cases
19
Behavioral changes in 15% of non-eloquent area glioblastomas
20
Gait instability in 12% of infratentorial glioblastomas
21
Anosmia rare but occurs in 2% of anterior frontal glioblastomas
22
Urinary incontinence as a late symptom in 5% due to frontal involvement
23
40% of patients experience progressive neurological deterioration
24
Mass effect symptoms like papilledema in 30% on exam
25
Psychosis-like symptoms in <1% of glioblastoma cases
26
Hearing loss in 3% of temporal glioblastomas invading auditory pathways
27
Facial weakness in 7% of pontine glioblastomas
28
Vertigo reported in 5% of CPA angle glioblastomas
Interpretation
Clinical Presentation Interpretation
In the clinical presentation of glioblastoma, headache stands out as the most common initial symptom in 50 to 60% of patients, while seizures appear in 30 to 50% and other neurologic deficits like cognitive impairment occur in about 40%, underscoring how frequently patients present with both general and focal brain symptoms.
02 · Category
Epidemiology30 stats
01
The age-adjusted incidence rate of glioblastoma in the United States from 2015-2019 was 3.19 per 100,000 person-years
02
Glioblastoma accounts for 14.3% of all primary brain tumors and 48.6% of all malignant primary brain tumors in the US (CBTRUS 2021)
03
The median age at diagnosis for glioblastoma is 65 years, with 75% of cases occurring in individuals over 55 years old
04
Males have a 1.6 times higher incidence rate of glioblastoma compared to females (3.93 vs 2.49 per 100,000)
05
In Europe, the incidence of glioblastoma is approximately 3-4 per 100,000 population annually
06
Glioblastoma represents 49% of all gliomas diagnosed in adults
07
The incidence of glioblastoma has remained stable over the past decade at around 3.2 per 100,000 in high-income countries
08
African Americans have a slightly lower incidence of glioblastoma (2.91 per 100,000) compared to Whites (3.26 per 100,000)
09
Ionizing radiation exposure increases glioblastoma risk by 2-5 fold
10
No strong association exists between cell phone use and glioblastoma incidence (pooled RR 0.98)
11
Pediatric glioblastoma incidence is 0.1-0.2 per 100,000 children under 15
12
In Asia, glioblastoma incidence is lower at 0.59 per 100,000 compared to Western countries
13
Glioblastoma prevalence in the US is estimated at 124,000 cases in 2022
14
Occupational exposure to pesticides is linked to a 1.4-fold increased risk of glioblastoma
15
Familial aggregation occurs in less than 5% of glioblastoma cases
16
The highest incidence of glioblastoma is in Denmark at 5.52 per 100,000
17
Glioblastoma incidence peaks in the 65-74 age group at 12.5 per 100,000
18
HIV patients have a 1.5 times higher risk of glioblastoma
19
Annual glioblastoma diagnoses in the US: approximately 13,000 new cases
20
Women have a better survival rate post-glioblastoma diagnosis (HR 0.87)
21
Glioblastoma is rare before age 40, comprising only 10% of cases
22
Southeast Asian populations show glioblastoma incidence of 0.3 per 100,000
23
Smoking is not a significant risk factor for glioblastoma (OR 1.05)
24
Glioblastoma mortality rate mirrors incidence at 3.15 per 100,000 in the US
25
Cowden syndrome increases glioblastoma lifetime risk to 3-6%
26
Urban residence is associated with 10% higher glioblastoma incidence
27
Glioblastoma accounts for 15% of brain cancers in adults over 45
28
Incidence in Hispanics is 2.8 per 100,000 vs 3.4 in non-Hispanics
29
Turcot syndrome type 1 raises glioblastoma risk by 30-fold
30
Global glioblastoma burden: 34,000 new cases annually (2018 GLOBOCAN)
Interpretation
Epidemiology Interpretation
From an epidemiology perspective, glioblastoma is relatively uncommon but consistently burdens adults, with an age-adjusted US incidence of 3.19 per 100,000 person-years and a median diagnosis age of 65 years where 75% of cases occur after age 55.
03 · Category
Pathology And Molecular Features29 stats
01
Glioblastoma is characterized by pseudopalisading necrosis in 90% of cases
02
IDH1/2 wild-type status is present in 90-95% of primary glioblastomas
03
EGFR amplification occurs in 40-60% of glioblastoma tumors
04
PTEN mutations are found in 25-40% of glioblastomas
05
MGMT promoter methylation frequency is 35-45% in glioblastoma
06
TERT promoter mutations in 80-90% of IDH-wildtype glioblastomas
07
Ki-67 proliferation index averages 15-20% in glioblastoma
08
Chromosome 7 polysomy in 70% and 10q loss in 70% of cases
09
PDGFRA amplification in 10-15% of glioblastomas
10
NF1 mutations occur in 20-25% of glioblastoma samples
11
Giant cell variant comprises 1-3% of glioblastomas with TP53 mutations
12
Sarcomatous features in gliosarcoma subtype (2% of GBMs)
13
Microvascular proliferation is a hallmark in 85% of high-grade gliomas like GBM
14
ATRX loss rare in primary GBM (5%) but common in IDH-mutant
15
H3F3A K27M mutations in <1% of adult glioblastomas
16
CDKN2A/B homozygous deletion in 50-55% of GBMs
17
BRAF V600E mutation in 1-2% of glioblastomas
18
Tumor mutational burden averages 2.5 mut/Mb in glioblastoma
19
Hypermutation phenotype in 2-5% due to POLE mutations
20
Mesenchymal subtype (29%) shows NF-κB pathway activation
21
Proneural subtype (28%) associated with IDH mutation (low in primary)
22
Classical subtype (31%) defined by EGFR amp and Chr7 gain
23
Neural subtype (6%) expresses neuron markers
24
G-CIMP phenotype in 15% linked to better prognosis
25
PI3K pathway alterations in 80-90% of glioblastomas
26
TP53 mutations in 28% of primary glioblastomas
27
MET amplification in 4-7% of GBM cases
28
IDH1 R132H mutation defines secondary GBM (5-10% of all)
29
Average tumor diameter at diagnosis is 4-6 cm
Interpretation
Pathology And Molecular Features Interpretation
Across pathology and molecular features, glioblastoma commonly shows pseudopalisading necrosis in about 90% of cases along with a predominantly IDH1/2 wild-type profile and frequent TERT promoter mutations in 80 to 90% of IDH-wildtype tumors, reflecting a strong, recurrent molecular pathology pattern.
More related reading
04 · Category
Prognosis And Survival30 stats
01
Median OS with standard therapy is 15 months, dropping to 9 months with age >60
02
5-year survival rate for glioblastoma is 6.9% overall (SEER 2015-2019)
03
IDH-mutant glioblastomas have 27-month median OS vs 14 months wild-type
04
MGMT methylation improves OS to 21.7 vs 12.7 months non-methylated
05
Gross total resection (GTR) OS 16.3 months vs 11.6 months STR
06
Young age (<50) median OS 22 months vs 12 months >70 years
07
Karnofsky performance status (KPS) >=70 predicts OS >12 months (HR 0.6)
08
Recursive partitioning analysis (RPA) class III: 17.1 months OS, class V: 5.7 months
09
Gliosarcoma subtype OS similar to GBM at 13 months
10
Long-term survivors (>5 years) comprise 5-10%, often with MGMT meth
11
Post-recurrence survival averages 6-9 months
12
1-year survival rate 37%, 2-year 17% (CBTRUS data)
13
Female sex confers 10-15% better OS (HR 0.85)
14
Multifocal GBM at diagnosis OS 8 months vs unifocal 15 months
15
Ventricular involvement reduces OS by 4 months
16
Proneural subtype OS 15.2 months vs mesenchymal 11.8 months
17
High Ki-67 (>15%) halves OS to 10 months
18
Secondary GBM from low-grade has OS 6-7 years vs primary 1 year
19
TTFields + TMZ/RT OS 20.9 months (EF-14 trial)
20
Elderly hypoRT + TMZ OS 9.3 months vs RT alone 7.6 months
21
Tumor volume >50 cc predicts OS <10 months
22
30-day postoperative mortality 2-5% in GBM resections
23
G-CIMP+ tumors OS 26.4 months median
24
KPS <60 OS 3-4 months regardless of treatment
25
EGFRvIII expression associated with poorer OS (HR 1.3)
26
Leptomeningeal spread at recurrence halves survival to 2 months
27
Pediatric GBM 5-year OS 20% vs 5% adults
28
Pretreatment neutrophil-lymphocyte ratio >4 predicts worse OS
29
Corpus callosum involvement OS 10 months median
30
Hypermutated GBM OS 22 months despite recurrence
Interpretation
Prognosis And Survival Interpretation
For prognosis and survival, glioblastoma typically has a median overall survival of only 15 months with standard therapy, but outcomes can almost double with favorable factors such as 27-month median OS for IDH-mutant tumors and 21.7 months with MGMT methylation compared with 14 months for wild-type and 12.7 months for non-methylated cases.
05 · Category
Treatment29 stats
01
Maximal safe resection is achieved in 30-40% of glioblastoma cases
02
Standard treatment includes temozolomide (TMZ) with radiotherapy yielding median OS of 14.6 months (Stupp protocol)
03
Gross total resection improves survival by 3-5 months compared to biopsy only
04
Bevacizumab extends PFS by 4 months (median 10.7 vs 6.4 months) but not OS
05
MGMT-methylated tumors respond better to TMZ (HR 0.53 for OS)
06
Hypofractionated RT (40 Gy/15 fx) equivalent to standard 60 Gy/30 fx in elderly
07
Tumor-treating fields (TTFields) add 5 months OS (20.9 vs 16.0 months)
08
Dose-dense TMZ schedules improve PFS in 25% recurrence cases
09
Laser interstitial thermal therapy (LITT) used in 10% inoperable cases
10
Carmustine wafers implanted in 5-10% of resected cavities
11
Proton beam therapy reduces neurocognitive decline by 20% vs photon RT
12
Immunotherapy checkpoint inhibitors (nivolumab) show 10% ORR in GBM
13
DCVax-L vaccine extends OS to 23.1 months in phase III
14
Stereotactic radiosurgery (SRS) for small recurrences (<3cm) PFS 6 months
15
Lomustine + TMZ rechallenge ORR 22% at recurrence
16
Fluorescence-guided surgery with 5-ALA increases GTR by 20%
17
Elderly (>70) short-course TMZ monotherapy OS 8.3 months
18
Regorafenib phase II OS 7.4 months at recurrence
19
Intra-arterial chemotherapy trials show 30% tumor reduction
20
CAR-T therapy targeting EGFRvIII in early trials PFS 3 months
21
Whole brain RT avoided; focal RT volumes average 200-300 cc
22
Neoadjuvant immunotherapy increases TILs by 50% in resected GBM
23
RTOG 0525 trial: dose-intensified TMZ no OS benefit
24
Oncolytic HSV (DNX-2401) 20% response in injected tumors
25
Pazopanib monotherapy PFS 3.2 months
26
Awake craniotomy enables 75% resection in eloquent areas
27
PCV chemotherapy inferior to TMZ in anaplastic gliomas but tested in GBM
28
Nano-particle albumin-bound paclitaxel in trials ORR 10%
29
Metabolic therapy (keto diet) adjunct PFS benefit in 20% retrospective
Interpretation
Treatment Interpretation
In glioblastoma treatment, maximizing extent of resection and using the right regimen matter most since maximal safe surgery is achieved in only 30 to 40 percent of cases yet gross total resection can improve survival by 3 to 5 months, while standard temozolomide plus radiotherapy yields a median overall survival of 14.6 months and patients with MGMT methylation have a better overall survival hazard ratio of 0.53.
report visual · Breakdown
Common glioblastoma symptoms at presentation
Headache and fatigue are among the most frequent initial symptoms, with seizures and cognitive impairment also commonly reported.
60%
Fatigue is reported by 60% of glioblastoma patients at presentation
40%
Cognitive impairment is reported in 40% of newly diagnosed glioblastoma patients
Reference
Cite This Report
This report is designed to be cited. We maintain stable URLs and versioned verification dates. Copy the format appropriate for your publication below.
APA
Julian Richter. (2026, February 13). Glioblastoma Statistics. Gitnux. https://gitnux.org/glioblastoma-statistics
MLA
Julian Richter. "Glioblastoma Statistics." Gitnux, 13 Feb 2026, https://gitnux.org/glioblastoma-statistics.
Chicago
Julian Richter. 2026. "Glioblastoma Statistics." Gitnux. https://gitnux.org/glioblastoma-statistics.
Sources & references
8 datasets cited across this report · attribution is report-level