Fig. 1

Histopathological and molecular features of pediatric high-grade gliomas, MYCN subgroup. The case #3 presented classical features of HGG-MYCN such as a dense proliferation composed of large cells with prominent nucleoli (HPS, magnification x400) with overexpression of p53 (magnification x400). The FISH analysis evidenced an amplification of both MYCN (orange signals) and ID2 (blue signals) loci (magnification x800). There was no Li-Fraumeni syndrome in this case. The case #7 presented classical features of HGG-MYCN such as a dense proliferation composed of large cells with prominent nucleoli and numerous mitoses (HPS, magnification x400) with overexpression of p53 (magnification x400). The FISH analysis evidenced an amplification of MYCN locus without amplification of ID2 gene (magnification x800). There was a context of Li-Fraumeni syndrome. FISH: Fluorescence in situ hybridization; HGG: high-grade glioma; HPS: Hematoxylin Phloxin Saffron; mut.: mutation. Black scale bars represent 50 μm