Table 3 Clinicopathological features of pediatric HGG subgroups.

Summary of major molecular and clinical characteristics of pediatric HGG subgroups as defined by a combination of DNA methylation profiles and genetic alterations. amp, amplification; del, deletion; mut, mutated; NA, as yet unclear; OS, overall survival; wt, wild type.

Methylation
subgroup
IDH mutK27 mutG34 mutHistone/IDH wt
Further
specification
H3.1 K27MH3.3 K27MH3.3 G34R/VMYCNPDGFRAEGFROthers
LocationHemispheric,
mostly
frontal lobe
Almost
exclusively
pons (DIPG)
Midline
(thalamus,
cerebellum, spine)
pons (DIPG)
HemisphericHemisphericHemisphericHemisphericHemispheric
Average ageTeenage/young
adult
~4.5 years~7 yearsTeenage/young
adult
~8 years~11 years~10 yearsNA
PrognosisIntermediate
median
OS >5 years
Poor median
OS ~15 months
Very poor
median OS
~10 months
Poor median
OS ~24 months
Poor median
OS ~14 months
Poor median
OS ~21 months
Intermediate
median OS
~44 months
NA
MutationsIDH1, TP53,
ATRX
HIST1H3A/B/C,
TP53, PPM1D,
ACVR1, PIK3R1,
PIK3CA
H3F3A, TP53,
PPM1D, ATRX,
PI3KR1, PIK3CA,
NF1, FGFR1, BRAF
H3F3A, TP53,
ATRX, PDGFRA
TP53TP53TP53TP53, PTEN,
PIK3CA
Copy number
aberrations
CCND/CDK amp
CDKN2A/B del
Various RTK amp
CCND/CDK amp
PDGFRA ampMYCN amp ID2
amp CDK4/6
amp Chr7 gain
PDGFRA
amp
EGFR amp
CDKN2A/B del
10q del
MET fusion/
amp NTRK
fusion
Other featuresMGMT methylation
occasional
hypermutation
phenotype
Global H3
K27me3 loss
Global H3
K27me3 loss
MGMT methylation
subtelomeric
hypomethylation
NANANANA