title: Pediatric rhabdoid meningioma: a morphological, immunohistochemical, ultrastructural and molecular case study.
abstract: Rhabdoid meningioma is an uncommon meningioma variant categorized as WHO grade III. The majority of cases occur in adulthood. Herein, we describe a right fronto-temporal rhabdoid meningioma affecting a 3-year-old boy. The lesion measured approximately 4 cm in diameter and incorporated the ipsilateral middle cerebral artery. Sub-total surgical excision of the mass was performed. Histologically, the tumor was mainly composed of globoid plump cells with inclusion-like eosinophilic cytoplasm, peripheral nuclei, prominent nucleoli and occasional intra-nuclear cytoplasmic pseudo-inclusion. The cells appeared in many areas loosely arranged and focally disclosed a papillary architecture. At immunohistochemistry, the tumor cells were EMA, vimentin, HHF35, PgR, INI-1 and p53 positive. The proliferative index (Mib-1) was 15% in the most positive areas. Ultrastructurally, tumoral cells showed an abundant cytoplasm, which was filled with numerous intermediate filaments. Desmosomal junctions were seen. RT-PCR revealed the presence of NF2 gene expression. Molecular study did not indicate alterations of the INI-1 gene, whereas it showed the presence of Pro72Arg in exon 4 at heterozygous state in the TP53 gene. Morphologic features along with immunohistochemical, ultrastructural and molecular results were consistent with the diagnosis of rhabdoid meningioma. The patient was treated with chemotherapy. The lesion remained stable after 33 months of follow-up. Rhabdoid meningiomas rarely occur in children. Owing to its rarity, each new case should be recorded to produce a better clinical, pathological, molecular, prognostic and therapeutic characterization of this lesion.
authors.affiliation: Department of Biomedicine, Careggi Hospital, Florence, Italy. ambuccoliero@unifi.it
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Buccoliero
authors.forename: Francesca
authors.initials: F
authors.lastname: Castiglione
authors.forename: Duccio
authors.initials: D
authors.lastname: Rossi Degl'Innocenti
authors.forename: Alessandro
authors.initials: A
authors.lastname: Franchi
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Sanzo
authors.forename: Valentina
authors.initials: V
authors.lastname: Cetica
authors.forename: Laura
authors.initials: L
authors.lastname: Giunti
authors.forename: Iacopo
authors.initials: I
authors.lastname: Sardi
authors.forename: Federico
authors.initials: F
authors.lastname: Mussa
authors.forename: Flavio
authors.initials: F
authors.lastname: Giordano
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Genitori
authors.forename: Gian Luigi
authors.initials: GL
authors.lastname: Taddei
mesh_terms: D002675:Child, Preschool; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics; D004252:DNA Mutational Analysis; D004268:DNA-Binding Proteins / Q000235:genetics; D016515:Genes, Neurofibromatosis 2; D016158:Genes, p53; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008577:Meningeal Neoplasms / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure*; D008579:Meningioma / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure*; D046529:Microscopy, Electron, Transmission; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018335:Rhabdoid Tumor / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure*; D000071796:SMARCB1 Protein; 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