Description
Primitive neuroectodermal tumors of the central nervous system (CNS PNETs) are highly aggressive, poorly differentiated embryonal tumors occurring predominantly in young children. Using DNA methylation and gene expression profiling we have demonstrated that a significant proportion of institutionally diagnosed CNS PNETs display molecular profiles indistinguishable from those of various other well defined CNS tumor entities, facilitating diagnosis and appropiate therapy for children with these tumors. From the remaining fraction of CNS PNETs, we have identified four distinct new CNS tumor entities extending to other neuroepithelial tumors, each associated with a recurrent genetic alteration and particular histopathological and clinical features. These molecular entities, designated CNS Neuroblastoma with FOXR2 activation (CNS NB FOXR2), CNS Ewing sarcoma family tumor with CIC alteration (CNS EFT CIC), CNS high grade neuroepithelial tumor with MN1 alteration (CNS HGNET MN1), and CNS high grade neuroepithelial tumor with BCOR alteration (CNS HGNET BCOR), will enable meaningful clinical trials and the development of therapeutic strategies for patients affected by these poorly differentiated CNS tumors.