Embryonal tumors with abundant neuropil and true rosettes (ETANTR) are rare pediatric embryonal neoplasms that combine features of neuroblastoma and ependymoblastoma. We report a distinct immunohistochemical-staining pattern of ETANTR in a 12-month-old baby who presented with a supratentorial mass. The tumor exhibited a characteristic biphasic pattern of neuropil-rich areas and patchy cellular neuropil-poor areas. The neoplastic cells in neuropil-rich areas are diffusely immunoreactive to chromogranin A, synaptophysin, neurofilament, and CD56, but show no immunoreactivity to nestin, SOX2, WT-1, β-catenin, and vimentin. While the cells in neuropil-poor areas, including ependymoblastic and Flexner-Wintersteiner rosettes, are diffusely immunoreactive to nestin, SOX2, WT-1, β-catenin, and vimentin but show no immunoreactivity to chromogranin A, synaptophysin, neurofilament, and CD56. Ependymoblastic rosettes show luminal membranous immunoreactivity to EMA. We believe that ETANTR has a distinct histologic and immunohistochemical pattern supporting the embryonal origin of this tumor with divergent neuroblastic and primitive glial differentiation.
|Journal||Applied Immunohistochemistry and Molecular Morphology|
|Publication status||Published - Jul 1 2016|
- embryonal tumor with abundant neuropil and true rosettes
- pediatric CNS neoplasms
ASJC Scopus subject areas
- Pathology and Forensic Medicine
- Medical Laboratory Technology