Fig. 3

Examination of an IDH-mutant astrocytoma case with differential methylation diagnosis. A Patient SU-125 developed a distant tumor recurrence (from frontal lobe to cerebellum) as shown by MRI scans. The primary tumor and paired recurrence were assigned to the IDH-wildtype subclass diffuse pediatric-type high-grade glioma, RTK1 subtype. Both tumors harbored IDH1 (R132) mutations by immunohistochemistry, B and exhibited a negative glioma CpG island methylator phenotype (G-CIMP; green) by hierarchical clustering of the IDH-mutant glioma samples with The Cancer Genome Atlas (TCGA) glioma samples [31] and glioblastoma, IDH-wildtype samples from Wenger et al. with a G-CIMP Negative signature (black) [38]. The tumor samples are color-coded by patient identity. Scale bars: 100 µm