• Miriam E Peckham, Anne G Osborn, Cheryl A Palmer, Amy Tsai, and Karen L Salzman.
• Department of Radiology and Imaging Sciences, University of Utah Health Sciences Center, Salt Lake City, UT.
• J Neuroimaging. 2019 Jan 1; 29 (1): 126-132.

Background And PurposeGliosarcoma (GSC) is an intra-axial lesion which often abuts a dural margin and is composed of glial and mesenchymal elements. This lesion is considered a variant of isocitrate dehydrogenase (IDH)-wild type glioblastoma (GBM). The purpose of this study is to evaluate the imaging and molecular features of GSC in a large patient cohort.MethodsPathology-proved GSC cases were collected from our quaternary care center spanning the last 16 years and IDH status was documented. Older GSC cases without prior immunohistochemical testing underwent tissue block staining to obtain IDH status. When available, p53, phosphate and tensin (PTEN), MIB-1, EGFR amplification, and MGMT methylation were recorded and imaging findings tabulated. Logistic regression analyses were performed to determine correlation of molecular markers and imaging characteristics.ResultsA total of 25 cases were identified (21 de novo, 4 post-treatment). All lesions contacted a dural, pial, or ependymal surface and were negative for an IDH R132H mutation, including postradiation GSC. In total, 16 of 16 cases showed nonamplification of EGFR/CEP7, 2 of 16 demonstrated MGMT methylation, and multiple lesions demonstrated p53 and PTEN mutations. Imaging features included areas of nodular thickening in necrotic lesions which appeared to abut the site of dural contact. There was no significant correlation of molecular markers with imaging characteristics.ConclusionGSC was IDH(-) in all cases, supporting the current understanding of this lesion being a wild-type GBM variant. Additional molecular markers demonstrated no significant correlation with imaging findings in this cohort.© 2018 by the American Society of Neuroimaging.

27 keywords...

hide…