Tumors diagnosed as cerebellar glioblastoma comprise distinct molecular entities

Table 1 Methylation (sub)class^a distribution of cerebellar and supratentorial WHO grade IV gliomas

methylation (sub)class^a	supratentorial	Percent	cerebellar	Percent
methylation (sub)class^a	n = 522	Percent	n = 42	Percent
GBM G34	37	7	0	0
GBM MES	127	24	4	10
GBM MID	23	4	11	26
GBM MYCN	18	3	3	7
GBM RTK I	72	14	8	19
GBM RTK II	171	33	2	5
GBM RTK III	9	2	1	2
DMG K27^b	33	6	7	17
A IDH^b	32	6	6	14

GBM IDH mut glioblastoma IDH mutant, DMG K27 diffuse midline glioma H3 K27 M mutant, GBM G34 glioblastoma IDH wildtype subclass H3 G34 mutant, GBM MYCN glioblastoma IDH wildtype subclass MYCN, GBM MES glioblastoma IDH wildtype subclass MES, GBM RTK I/II/III glioblastoma IDH wildtype subclass(es) RTK I/III/III, GBM MID glioblastoma IDH wildtype subclass midline, A IDH IDH mutant glioma subclass astrocytoma or high grade astrocytoma
^a Methylation class is defined as group of tumors with the same classifier diagnosis (= epigenetic subgroup) which was allotted to a tumor sample with a classifier score above 0.9
^b Frequencies of these tumors may be biased depending on the supplier diagnosis, the date of diagnosis and the availability and application of antibodies or sequencing methods detecting IDH and histone mutations

ISSN: 2051-5960