IDH2 and astrocytoma (excluding glioblastoma): IDH-mutant astrocytomas have previously been successfully stratified exclusively by global CNV level at initial biopsy/resection with a threshold of 10–15% of the genome (approximately 310–470 Megabase pairs (Mbp) with copy number change log2 ≥ 0.3) [3, 72, 97, 105].