title: Embryonal tumor with multilayered rosettes of the fourth ventricle: case report.
abstract: Embryonal tumor with multilayered rosettes (ETMR) is a recently described pathological entity. These primitive central nervous system tumors harbor amplification of the 19q13.42 locus and resultant overexpression of the LIN28A protein. Although the WHO currently recognizes 3 distinct histopathological entities-embryonal tumor with abundant neuropil and true rosettes (ETANTR), ependymoblastoma, and medulloepithelioma-recent studies indicate that these tumors have a common molecular profile and clinical course and that they are now classified as a single entity. Here the authors present a case of ETMR located in the fourth ventricle in a 12-month-old boy. The histopathology featured areas of neuropil-like stroma and highly cellular foci with characteristic multilayered rosettes. The authors discuss the clinical, radiological, and histopathological findings in this case and compare them with data in previously published cases in the literature. A review of studies assessing the molecular mechanisms underlying these tumors is also presented.
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Edmonson
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Kristin J
authors.initials: KJ
authors.lastname: Weaver
authors.affiliation: Pathology, University of Florida, Gainesville, Florida.
authors.forename: Jesse
authors.initials: J
authors.lastname: Kresak
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: David W
authors.initials: DW
authors.lastname: Pincus
keywords: AT/RT = atypical teratoid/rhabdoid tumor; ETANTR; ETANTR = embryonal tumor with abundant neuropil and true rosettes; ETMR; ETMR = embryonal tumor with multilayered rosettes; EVD = external ventricular drain; FISH = fluorescence in situ hybridization; HGG = high-grade glioma; LIN28A; PNET = primitive neuroectodermal tumor; POD = postoperative day; embryonal tumor; fourth ventricle tumor; miRNA = microRNA; microRNA; oncology