title: Central nervous system primitive neuroectodermal tumors: a clinicopathologic and genetic study of 33 cases.
abstract: Central nervous system (CNS) primitive neuroectodermal tumors (PNETs) include supratentorial, brain stem, and spinal cord tumors with medulloblastoma-like histopathology. The prognostic impact of various pathologic and genetic features has not been thoroughly investigated. After re-diagnosis of three infantile cases as atypical teratoid/rhabdoid tumor (AT/RT), 33 remaining CNS PNETs were retrieved for clinicopathologic and fluorescence in situ hybridization studies. Anaplastic and/or large cell features were seen in 18 of 33 (55%) examples and survival was decreased in these patients (P = 0.036). MYCN or MYCC gene amplifications were noted in about half, with a trend towards decreased survival (P = 0.112). Polysomies of chromosomes 2 and 8 were each individually associated with decreased survival in children, with an even stronger association when combined (P = 0.013). Neither EWS gene rearrangements, nor AT/RT-like 22q deletions were encountered. We conclude that in CNS PNET: (i) routine application of INI1 immunohistochemistry helps rule out AT/RT, particularly in infants; (ii) MYC gene amplifications (especially MYCN) are common; (iii) involvement of CNS parenchyma by Ewing sarcoma/peripheral PNET is rare enough that EWS gene testing is not necessary unless significant dural involvement is present; and (iv) both anaplastic/large cell features and polysomies of 2 and 8 are associated with more aggressive clinical behavior.
authors.affiliation: Department of Pathology, Cedar Sinai Medical Center, Los Angeles, Calif, USA.
authors.forename: Amir
authors.initials: A
authors.lastname: Behdad
authors.forename: Arie
authors.initials: A
authors.lastname: Perry
mesh_terms: D000293:Adolescent; D000328:Adult; D000782:Aneuploidy; D001932:Brain Neoplasms / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D002889:Chromosomes, Human, Pair 2; D002892:Chromosomes, Human, Pair 22; D002898:Chromosomes, Human, Pair 8; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D000071447:N-Myc Proto-Oncogene Protein; D018242:Neuroectodermal Tumors, Primitive / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology*; D009687:Nuclear Proteins / Q000235:genetics; D015513:Oncogene Proteins / Q000235:genetics; D034802:RNA-Binding Protein EWS / Q000235:genetics; D018335:Rhabdoid Tumor / Q000175:diagnosis / Q000235:genetics / Q000473:pathology; D013120:Spinal Cord Neoplasms / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology*; D013724:Teratoma / Q000175:diagnosis / Q000235:genetics / Q000473:pathology; D055815:Young Adult
chemical_list: C459801:MYCN protein, human; D000071447:N-Myc Proto-Oncogene Protein; D009687:Nuclear Proteins; D015513:Oncogene Proteins; D034802:RNA-Binding Protein EWS