Pediatric-type high-grade neuroepithelial tumors with CIC gene fusion share a common DNA methylation signature

Pediatric neoplasms in the central nervous system show an extensive clinical and molecular heterogeneity. Molecular genetic testing contributes to accurate diagnosis and enables an optimal clinical management of affected children. Unsupervised visualization of genome-wide DNA methylation array data revealed a molecularly distinct type of pediatric high-grade neuroepithelial tumor with fusions involving the capicua transcriptional repressor (CIC) gene, with the most common fusion being CIC::LEUTX. Histopathological review demonstrated a morphologically heterogeneous group of high-grade neuroepithelial tumors with positive immunostaining for markers of glial differentiation in combination with weak and focal expression of synaptophysin, CD56 and CD99. In summary, we expand the spectrum of pediatric-type tumors of the CNS by reporting a previously uncharacterized group of rare high-grade neuroepithelial tumors that share a common DNA methylation signature and recurrent gene fusions involving the transcriptional repressor CIC. DNA methylation signature