TY - JOUR A1 - Stichel, D A1 - Ebrahimi, A A1 - Reuss, D A1 - Schrimpf, D A1 - Ono, T A1 - Shirahata, M A1 - Reifenberger, G A1 - Weller, M A1 - Hänggi, D A1 - Wick, W A1 - Herold-Mende, C A1 - Westphal, M A1 - Brandner, S A1 - Pfister, SM A1 - Capper, D A1 - Sahm, F A1 - von Deimling, A JF - Acta Neuropathologica SN - 1432-0533 UR - https://doi.org/10.1007/s00401-018-1905-0 N1 - This version is the author accepted manuscript. For information on re-use, please refer to the publisher?s terms and conditions. IS - 5 SP - 793 VL - 136 KW - 7+/10q? KW - 7+/10? KW - Astrocytoma KW - Chromosome 10 loss KW - Chromosome 7 gain KW - EGFR amplification KW - Glioblastoma KW - Pleomorphic xanthoastrocytoma KW - TERT promoter mutation ID - discovery10055666 N2 - EGFR amplification (EGFRamp), the combination of gain of chromosome 7 and loss of chromosome 10 (7+/10-), and TERT promoter mutation (pTERTmut) are alterations frequently observed in adult IDH-wild-type (IDHwt) glioblastoma (GBM). In the absence of endothelial proliferation and/or necrosis, these alterations currently are considered to serve as a surrogate for upgrading IDHwt diffuse or anaplastic astrocytoma to GBM. Here, we set out to determine the distribution of EGFRamp, 7+/10-, and pTERTmut by analyzing high-resolution copy-number profiles and next-generation sequencing data of primary brain tumors. In addition, we addressed the question whether combinations of partial gains on chromosome 7 and partial losses on chromosome 10 exhibited a diagnostic and prognostic value similar to that of complete 7+/10-. Several such combinations proved relevant and were combined as the 7/10 signature. Our results demonstrate that EGFRamp and the 7/10 signature are closely associated with IDHwt GBM. In contrast, pTERTmut is less specific for IDHwt GBM. We conclude that, in the absence of endothelial proliferation and/or necrosis, the detection of EGFRamp is a very strong surrogate marker for the diagnosis of GBM in IDHwt diffuse astrocytic tumors. The 7/10 signature is also a strong surrogate marker. However, care should be taken to exclude pleomorphic xanthoastrocytoma. pTERTmut is less restricted to this entity and needs companion analysis by other molecular markers to serve as a surrogate for diagnosing IDHwt GBM. A combination of any two of EGFRamp, the 7/10 signature and pTERTmut, is highly specific for IDHwt GBM and the combination of all three alterations is frequent and exclusively seen in IDHwt GBM. EP - 803 AV - public Y1 - 2018/11// TI - Distribution of EGFR amplification, combined chromosome 7 gain and chromosome 10 loss, and TERT promoter mutation in brain tumors and their potential for the reclassification of IDHwt astrocytoma to glioblastoma ER -