Combined ATRX/IDH1 immunohistochemistry predicts genotype of oligoastrocytomas.
Histopathology
; 68(2): 272-8, 2016 Jan.
Article
em En
| MEDLINE
| ID: mdl-26016385
ABSTRACT
AIMS:
To assess whether in oligoastrocytomas ATRX deficiency, as a surrogate of the alternative lengthening of telomeres (ALT) pathway, has a role in predicting the presence or absence of loss of heterozygosity (LOH) of 1p and 19q, the genetic signature of oligodendroglial differentiation and a favourable prognostic marker. METHODS ANDRESULTS:
A series of 54 oligoastrocytomas were investigated by immunohistochemistry as well as microsatellite analysis for LOH 1p19q. Genetic findings were correlated with morphological assessment.CONCLUSIONS:
ATRX deficiency was mutually exclusive with LOH. Conversely, ATRX-proficient tumours immunoreactive for R132H-mutant isocitrate dehydrogenase 1 (IDH1) showed a high rate (85%) of LOH. A more oligodendroglioma-like morphology was associated with a higher rate of LOH even in the morphologically ambiguous group of oligoastrocytomas. Our findings support the concept that oligoastrocytomas represent a morphological grey zone, rather than a group of truly 'mixed' or 'intermediate' tumours. More precise classification of diffuse gliomas may also improve grading of borderline cases. We propose an immunohistochemical algorithm for classification of morphologically ambiguous diffuse gliomas.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oligodendroglioma
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Repetições de Microssatélites
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Perda de Heterozigosidade
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Homeostase do Telômero
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Proteína Nuclear Ligada ao X
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Isocitrato Desidrogenase
Tipo de estudo:
Prognostic_studies
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Risk_factors_studies
Limite:
Adult
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Aged
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Aged80
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Histopathology
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
Suíça