title: Embryonal tumor with abundant neuropil and true rosettes: a report of three cases of a rare tumor, with an unusual case showing rhabdomyoblastic and melanocytic differentiation.
abstract: Embryonal tumor with abundant neuropil and true rosettes (ETANTR) is an increasingly recognized entity that belongs to the family of embryonal tumors of the CNS. The authors present three cases of this rare tumor that were encountered at King Hussein Cancer Center, Amman, Jordan. Discussion of the clinicopathological findings is presented along with a recent literature review. Sixteen-, 57- and 30-month-old children presented with tumors located in the pineal gland, the right fronto- parieto-temporal region and the cerebellum, respectively. The findings of hypocellular neuropil as well as the characteristic ependymoblastic rosettes were seen. In addition the third case showed an abnormal combination of patterns including melanocytic and rhabdomyoblastic differentiation. The tumors stained positively for synaptophysin in the neuropil and small cell component, while the ependymoblastic rosettes stained for vimentin only. Epithelial membrane antigen and CD99 were negative in all components. One of the cases showed tetraploidy of chromosome 2. All cases exhibited an aggressive course. This is a rare and recently recognized tumor with dismal outcome, and reporting of additional new cases should help in gaining more knowledge about it.
authors: Department of Pathology, King Hussein Cancer Center (KHCC), Amman, Jordan. mhussaini@khcc.jo
authors: Maysa
authors: M
authors: Al-Hussaini
authors: Najiyah
authors: N
authors: Abuirmeileh
authors: Maisa
authors: M
authors: Swaidan
authors: Usama
authors: U
authors: Al-Jumaily
authors: Haytham
authors: H
authors: Rajjal
authors: Awni
authors: A
authors: Musharbash
authors: Sameh
authors: S
authors: Hashem
authors: Iyad
authors: I
authors: Sultan
mesh_terms: D001932:Brain Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000628:therapy; D002454:Cell Differentiation; D002675:Child, Preschool; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D008297:Male; D009373:Neoplasms, Germ Cell and Embryonal / Q000378:metabolism / Q000473:pathology* / Q000628:therapy; D019581:Neuropil / Q000473:pathology