title: Atypical teratoid/rhabdoid tumor with ganglioglioma-like differentiation: case report and review of the literature.
abstract: Atypical teratoid/rhabdoid tumor (AT/RT) is a highly aggressive embryonal tumor of the central nervous system, which typically affects young children. A characteristic feature of AT/RT is a polyphenotypic immunoprofile and ultrastructural diversity. The morphologic and antigenic heterogeneity of AT/RT give it the potential to mimic other embryonal central nervous system tumors, epithelial neoplasms or mesenchymal tumors. Alternatively, "collision-type" tumors have been published, in which AT/RT coexists with a separate low-grade central nervous system tumor. Here, we report a case of AT/RT with morphologic and immunohistochemical evidence of extensive ganglioglioma-like differentiation with only a small focal primitive component and minimal rhabdoid cytology. Fluorescence in situ hybridization and immunohistochemistry demonstrated INI1/BAF47 gene/protein losses in both histologic components. To the best of our knowledge, this is the first reported case of AT/RT with extensive ganglioglioma-like differentiation. This unique case supports the notion that routine application of INI1 stains/in situ hybridization can capture AT/RT with unexpected patterns of differentiation.
authors.affiliation: Department of Pathology, Dell Children's Medical Center, Austin, TX 78723, USA. Electronic address: chandra.krishnan@yahoo.com.
authors.forename: Chandra
authors.initials: C
authors.lastname: Krishnan
authors.forename: Hannes
authors.initials: H
authors.lastname: Vogel
authors.forename: Arie
authors.initials: A
authors.lastname: Perry
mesh_terms: D001932:Brain Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D002454:Cell Differentiation; D002675:Child, Preschool; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics; D005260:Female; D018303:Ganglioglioma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D018335:Rhabdoid Tumor / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D000071796:SMARCB1 Protein; D013724:Teratoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D014157:Transcription Factors / Q000235:genetics
chemical_list: D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D000071796:SMARCB1 Protein; C513266:SMARCB1 protein, human; D014157:Transcription Factors
keywords: Atypical teratoid rhabdoid tumor; Ganglioglioma; INI1; Pediatric brain tumor