CDKN2A and astrocytoma (excluding glioblastoma): Although the exact reasons for the higher chromosomal integrity in TG01 could not be defined within the scope of this study, the results are consistent with the previous notion of the GLASS consortium that the progression of IDHmut astrocytomas follows two distinct routes characterized by either a homozygous deletion of CDKN2A or hypermutation which is typically TMZ-induced [10].