Compendium of Cancer Genome Aberrations

CNS5:Diffuse astrocytoma, MYB- or MYBL1-altered: Difference between revisions

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{{DISPLAYTITLE:Diffuse astrocytoma, MYB- or MYBL1-altered}}
{{DISPLAYTITLE:Diffuse astrocytoma, MYB- or MYBL1-altered}}


[[CNS5:Table_of_Contents|Central Nervous System Tumours(WHO Classification, 5th ed.)]]
[[CNS5:Table_of_Contents|Central Nervous System Tumours (WHO Classification, 5th ed.)]]


{{Under Construction}}
{{Under Construction}}
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Scott C. Smith, PhD, FACMG; SUNY Upstate Medical University
Scott C. Smith, PhD, FACMG; SUNY Upstate Medical University


==WHO Classification of Disease==
==WHO Classification of Disease==
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|}
|}


==Definition / Description of Disease==
==Related Terminology==
 
Diffuse astrocytoma, ''MYB'' or ''MYBL1''-altered is one of several newly recognized tumor types in the 5<sup>th</sup> edition of the ''WHO Classification of Tumors of the Central Nervous System''. The newly recognized classifications were in response to advances in understanding of paediatric-type gliomas, facilitated by an increased molecular characterisation of these tumours. Diffuse astrocytoma, MYB or MYBL1-altered is a subset of diffuse low-grade glioma with amplifications, structural variants, and fusions involving the ''MYB'' and ''MYBL1'' protooncogenes. Diffuse astrocytoma, MYB or MYBL1-altered subtypes are without characteristic histological features of angiocentric glioma<ref>{{Cite journal|last=Slegers|first=Rutger Juriaan|last2=Blumcke|first2=Ingmar|date=2020-03-09|title=Low-grade developmental and epilepsy associated brain tumors: a critical update 2020|url=https://pubmed.ncbi.nlm.nih.gov/32151273|journal=Acta Neuropathologica Communications|volume=8|issue=1|pages=27|doi=10.1186/s40478-020-00904-x|issn=2051-5960|pmc=7063704|pmid=32151273}}</ref><ref>{{Cite journal|last=Bandopadhayay|first=Pratiti|last2=Ramkissoon|first2=Lori A.|last3=Jain|first3=Payal|last4=Bergthold|first4=Guillaume|last5=Wala|first5=Jeremiah|last6=Zeid|first6=Rhamy|last7=Schumacher|first7=Steven E.|last8=Urbanski|first8=Laura|last9=O'Rourke|first9=Ryan|date=2016-03|title=MYB-QKI rearrangements in angiocentric glioma drive tumorigenicity through a tripartite mechanism|url=https://pubmed.ncbi.nlm.nih.gov/26829751|journal=Nature Genetics|volume=48|issue=3|pages=273–282|doi=10.1038/ng.3500|issn=1546-1718|pmc=4767685|pmid=26829751}}</ref>. A related group of diffuse gliomas, the isomorphic glioma, occur predominantly in adults and are typically well-differentiated, low to moderately cellular, comprised of astrocytes with rounded nuclei and regular chromatin structures, and have low proliferative indices<ref>{{Cite journal|last=Wefers|first=Annika K.|last2=Stichel|first2=Damian|last3=Schrimpf|first3=Daniel|last4=Coras|first4=Roland|last5=Pages|first5=Mélanie|last6=Tauziède-Espariat|first6=Arnault|last7=Varlet|first7=Pascale|last8=Schwarz|first8=Daniel|last9=Söylemezoglu|first9=Figen|date=2020-01|title=Isomorphic diffuse glioma is a morphologically and molecularly distinct tumour entity with recurrent gene fusions of MYBL1 or MYB and a benign disease course|url=https://pubmed.ncbi.nlm.nih.gov/31563982|journal=Acta Neuropathologica|volume=139|issue=1|pages=193–209|doi=10.1007/s00401-019-02078-w|issn=1432-0533|pmc=7477753|pmid=31563982}}</ref><ref>{{Cite journal|last=Chiang|first=Jason|last2=Harreld|first2=Julie H.|last3=Tinkle|first3=Christopher L.|last4=Moreira|first4=Daniel C.|last5=Li|first5=Xiaoyu|last6=Acharya|first6=Sahaja|last7=Qaddoumi|first7=Ibrahim|last8=Ellison|first8=David W.|date=2019-12|title=A single-center study of the clinicopathologic correlates of gliomas with a MYB or MYBL1 alteration|url=https://pubmed.ncbi.nlm.nih.gov/31595312|journal=Acta Neuropathologica|volume=138|issue=6|pages=1091–1092|doi=10.1007/s00401-019-02081-1|issn=1432-0533|pmc=7467132|pmid=31595312}}</ref>. These adult diffuse gliomas exhibit alterations of ''MYBL1'' rather than ''MYB'' . Gene fusions with multiple partners characterize the pediatric ''MYB'' or ''MYBL1-''altered gliomas<ref>{{Cite journal|last=Ramkissoon|first=Lori A.|last2=Horowitz|first2=Peleg M.|last3=Craig|first3=Justin M.|last4=Ramkissoon|first4=Shakti H.|last5=Rich|first5=Benjamin E.|last6=Schumacher|first6=Steven E.|last7=McKenna|first7=Aaron|last8=Lawrence|first8=Michael S.|last9=Bergthold|first9=Guillaume|date=2013-05-14|title=Genomic analysis of diffuse pediatric low-grade gliomas identifies recurrent oncogenic truncating rearrangements in the transcription factor MYBL1|url=https://pubmed.ncbi.nlm.nih.gov/23633565|journal=Proceedings of the National Academy of Sciences of the United States of America|volume=110|issue=20|pages=8188–8193|doi=10.1073/pnas.1300252110|issn=1091-6490|pmc=3657784|pmid=23633565}}</ref><ref>{{Cite journal|last=Barinfeld|first=Orit|last2=Zahavi|first2=Alon|last3=Weiss|first3=Shirel|last4=Toledano|first4=Helen|last5=Michowiz|first5=Shalom|last6=Goldenberg-Cohen|first6=Nitza|date=2022|title=Genetic Alteration Analysis of IDH1, IDH2, CDKN2A, MYB and MYBL1 in Pediatric Low-Grade Gliomas|url=https://pubmed.ncbi.nlm.nih.gov/35574540|journal=Frontiers in Surgery|volume=9|pages=880048|doi=10.3389/fsurg.2022.880048|issn=2296-875X|pmc=9096721|pmid=35574540}}</ref>. The most frequently identified fusion is with ''QKI''<ref>{{Cite journal|last=Suh|first=Ye Yoon|last2=Lee|first2=Kwanghoon|last3=Shim|first3=Yu-Mi|last4=Phi|first4=Ji Hoon|last5=Park|first5=Chul-Kee|last6=Kim|first6=Seung-Ki|last7=Choi|first7=Seung Hong|last8=Yun|first8=Hongseok|last9=Park|first9=Sung-Hye|date=2023-02-21|title=MYB/MYBL1::QKI fusion-positive diffuse glioma|url=https://pubmed.ncbi.nlm.nih.gov/36592415|journal=Journal of Neuropathology and Experimental Neurology|volume=82|issue=3|pages=250–260|doi=10.1093/jnen/nlac123|issn=1554-6578|pmc=9941827|pmid=36592415}}</ref><ref>{{Cite journal|last=Jain|first=Payal|last2=Resnick|first2=Adam C.|date=2017-03-04|title=MYB-QKI drives childhood brain tumors via tripartite mechanism|url=https://pubmed.ncbi.nlm.nih.gov/27973981|journal=Cell Cycle (Georgetown, Tex.)|volume=16|issue=5|pages=390–391|doi=10.1080/15384101.2016.1260990|issn=1551-4005|pmc=5351923|pmid=27973981}}</ref>''.'' The ''MYB'' or ''MYBL1-''altered diffuse gliomas in both children and adults are generally indolent and behave in a WHO grade 1 fashion.
 
==Clinical Features==


Medically refractory epilepsy since childhood.
{| class="wikitable"
{| class="wikitable"
|'''Signs and Symptoms'''
|+
|History of epilepsy or seizure
|Acceptable
Magnetic resonance imaging (MRI): well-delineated, occasionally infiltrative-appearing, non-enhancing T1-hypointense, T2-fluid attenuated inversion recovery-hyperintense lesion without restricted diffusion<ref>{{Cite journal|last=Fabbri|first=Viscardo Paolo|last2=Caporalini|first2=Chiara|last3=Asioli|first3=Sofia|last4=Buccoliero|first4=Annamaria|date=2022-12|title=Paediatric-type diffuse low-grade gliomas: a clinically and biologically distinct group of tumours with a favourable outcome|url=https://pubmed.ncbi.nlm.nih.gov/36534420|journal=Pathologica|volume=114|issue=6|pages=410–421|doi=10.32074/1591-951X-828|issn=1591-951X|pmc=9763978|pmid=36534420}}</ref>
|N/A
|-
|-
|'''Laboratory Findings'''
|Not Recommended
|Genetics: Negative for ''IDH1'' p.R132H, ''BRAF'' p.V600E; positive for ''MYBL1'' or ''MYB'' rearrangement, amplification, or copy number change
|Isomorphic astrocytoma variant; isomorphic diffuse glioma
|}
 
==Sites of Involvement==
 
Supratentorial (adult), cortical and subcortical regions of the cerebral cortex (pediatric)<ref>{{Cite journal|last=Fabbri|first=Viscardo Paolo|last2=Caporalini|first2=Chiara|last3=Asioli|first3=Sofia|last4=Buccoliero|first4=Annamaria|date=2022-12|title=Paediatric-type diffuse low-grade gliomas: a clinically and biologically distinct group of tumours with a favourable outcome|url=https://pubmed.ncbi.nlm.nih.gov/36534420|journal=Pathologica|volume=114|issue=6|pages=410–421|doi=10.32074/1591-951X-828|issn=1591-951X|pmc=9763978|pmid=36534420}}</ref>
 
==Morphologic Features==
 
Histomorphology: minimally to moderately hypercellular tumor; diffuse infiltration by monomorphic cells with ovoid to elongated nuclei, scant cytoplasm, fibrillary background<ref>{{Cite journal|last=Fabbri|first=Viscardo Paolo|last2=Caporalini|first2=Chiara|last3=Asioli|first3=Sofia|last4=Buccoliero|first4=Annamaria|date=2022-12|title=Paediatric-type diffuse low-grade gliomas: a clinically and biologically distinct group of tumours with a favourable outcome|url=https://pubmed.ncbi.nlm.nih.gov/36534420|journal=Pathologica|volume=114|issue=6|pages=410–421|doi=10.32074/1591-951X-828|issn=1591-951X|pmc=9763978|pmid=36534420}}</ref><ref>{{Cite journal|last=Suh|first=Ye Yoon|last2=Lee|first2=Kwanghoon|last3=Shim|first3=Yu-Mi|last4=Phi|first4=Ji Hoon|last5=Park|first5=Chul-Kee|last6=Kim|first6=Seung-Ki|last7=Choi|first7=Seung Hong|last8=Yun|first8=Hongseok|last9=Park|first9=Sung-Hye|date=2023-02-21|title=MYB/MYBL1::QKI fusion-positive diffuse glioma|url=https://pubmed.ncbi.nlm.nih.gov/36592415|journal=Journal of Neuropathology and Experimental Neurology|volume=82|issue=3|pages=250–260|doi=10.1093/jnen/nlac123|issn=1554-6578|pmc=9941827|pmid=36592415}}</ref>
 
==Immunophenotype==
 
Positivity for GFAP, below 1% Ki-67 index, negative for OLIG2 and IDH1 R132H<ref>{{Cite journal|last=Wefers|first=Annika K.|last2=Stichel|first2=Damian|last3=Schrimpf|first3=Daniel|last4=Coras|first4=Roland|last5=Pages|first5=Mélanie|last6=Tauziède-Espariat|first6=Arnault|last7=Varlet|first7=Pascale|last8=Schwarz|first8=Daniel|last9=Söylemezoglu|first9=Figen|date=2020-01|title=Isomorphic diffuse glioma is a morphologically and molecularly distinct tumour entity with recurrent gene fusions of MYBL1 or MYB and a benign disease course|url=https://pubmed.ncbi.nlm.nih.gov/31563982|journal=Acta Neuropathologica|volume=139|issue=1|pages=193–209|doi=10.1007/s00401-019-02078-w|issn=1432-0533|pmc=7477753|pmid=31563982}}</ref>
 
{| class="wikitable sortable"
|-
!Finding!!Marker
|-
|Positive (universal)||GFAP<span lang="EN-US">Scott C. Smith,
 
PhD, FACMG; SUNY Upstate Medical University
|-
|Positive (subset)||Ki-67 index below 1%
|-
|Negative (universal)||OLIG2, IDH1 R132H
|}
|}


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'''Add content below into table above''' -      
''MYB'' or ''MYBL1'' rearrangement
''MYB'' or ''MYBL1'' rearrangement


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{| class="wikitable sortable"
{| class="wikitable sortable"
|-
|-
!Chr #!!'''Gain, Loss, Amp, LOH'''!!'''Minimal Region Cytoband and/or Genomic Coordinates [Genome Build; Size]'''!!'''Relevant Gene(s)'''
!Chr #!!Gain, Loss, Amp, LOH!!Minimal Region Cytoband and/or Genomic Coordinates [Genome Build; Size]!!Relevant Gene(s)
!'''Diagnostic, Prognostic, and Therapeutic Significance - D, P, T'''
!Diagnostic, Prognostic, and Therapeutic Significance - D, P, T
!'''Established Clinical Significance Per Guidelines - Yes or No (Source)'''
!Established Clinical Significance Per Guidelines - Yes or No (Source)
!'''Clinical Relevance Details/Other Notes'''
!Clinical Relevance Details/Other Notes
|-
|-
|<span class="blue-text">EXAMPLE:</span>
|<span class="blue-text">EXAMPLE:</span>
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'''Add content below into table above''' -      
''MYB'' or ''MYBL1'' copy number variation as identified by chromosomal microarray or FISH
''MYB'' or ''MYBL1'' copy number variation as identified by chromosomal microarray or FISH


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!Chromosomal Pattern
!Chromosomal Pattern
!Molecular Pathogenesis
!Molecular Pathogenesis
!'''Prevalence -'''
!Prevalence -  
'''Common >20%, Recurrent 5-20% or Rare <5% (Disease)'''
Common >20%, Recurrent 5-20% or Rare <5% (Disease)
!'''Diagnostic, Prognostic, and Therapeutic Significance - D, P, T'''
!Diagnostic, Prognostic, and Therapeutic Significance - D, P, T
!'''Established Clinical Significance Per Guidelines - Yes or No (Source)'''
!Established Clinical Significance Per Guidelines - Yes or No (Source)
!'''Clinical Relevance Details/Other Notes'''
!Clinical Relevance Details/Other Notes
|-
|-
|<span class="blue-text">EXAMPLE:</span>
|<span class="blue-text">EXAMPLE:</span>
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'''Add content below into table above''' -      
Possible detection of double minutes or homogeneously stained regions by G-banding for amplification; will require confirmation of being associated with MYB or MYBL (likely by chromosomal microarray)
Possible detection of double minutes or homogeneously stained regions by G-banding for amplification; will require confirmation of being associated with MYB or MYBL (likely by chromosomal microarray)


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|Overexpression  of MYB/MYBL1
|Overexpression  of MYB/MYBL1
|}
|}


==Genetic Diagnostic Testing Methods==
==Genetic Diagnostic Testing Methods==


Sequencing, PCR, RT-PCR, chromosomal microarray, FISH, possibly detection of double minutes or homogenously stained regions by G-banding
Sequencing, PCR, RT-PCR, chromosomal microarray, FISH, possibly detection of double minutes or homogenously stained regions by G-banding
==Familial Forms==
N/A
==Additional Information==
This disease is <u>defined/characterized</u> as detailed below:
* Diffuse astrocytoma, ''MYB'' or ''MYBL1''-altered is one of several newly recognized tumor types in the 5<sup>th</sup> edition of the ''WHO Classification of Tumors of the Central Nervous System''. The newly recognized classifications were in response to advances in understanding of pediatric-type gliomas, facilitated by an increased molecular characterization of these tumors. Diffuse astrocytoma, MYB or MYBL1-altered is a subset of diffuse low-grade glioma with amplifications, structural variants, and fusions involving the ''MYB'' and ''MYBL1'' protooncogenes. Diffuse astrocytoma, MYB or MYBL1-altered subtypes are without characteristic histological features of angiocentric glioma<ref>{{Cite journal|last=Slegers|first=Rutger Juriaan|last2=Blumcke|first2=Ingmar|date=2020-03-09|title=Low-grade developmental and epilepsy associated brain tumors: a critical update 2020|url=https://pubmed.ncbi.nlm.nih.gov/32151273|journal=Acta Neuropathologica Communications|volume=8|issue=1|pages=27|doi=10.1186/s40478-020-00904-x|issn=2051-5960|pmc=7063704|pmid=32151273}}</ref><ref>{{Cite journal|last=Bandopadhayay|first=Pratiti|last2=Ramkissoon|first2=Lori A.|last3=Jain|first3=Payal|last4=Bergthold|first4=Guillaume|last5=Wala|first5=Jeremiah|last6=Zeid|first6=Rhamy|last7=Schumacher|first7=Steven E.|last8=Urbanski|first8=Laura|last9=O'Rourke|first9=Ryan|date=2016-03|title=MYB-QKI rearrangements in angiocentric glioma drive tumorigenicity through a tripartite mechanism|url=https://pubmed.ncbi.nlm.nih.gov/26829751|journal=Nature Genetics|volume=48|issue=3|pages=273–282|doi=10.1038/ng.3500|issn=1546-1718|pmc=4767685|pmid=26829751}}</ref>. A related group of diffuse gliomas, the isomorphic glioma, occur predominantly in adults and are typically well-differentiated, low to moderately cellular, comprised of astrocytes with rounded nuclei and regular chromatin structures, and have low proliferative indices<ref>{{Cite journal|last=Wefers|first=Annika K.|last2=Stichel|first2=Damian|last3=Schrimpf|first3=Daniel|last4=Coras|first4=Roland|last5=Pages|first5=Mélanie|last6=Tauziède-Espariat|first6=Arnault|last7=Varlet|first7=Pascale|last8=Schwarz|first8=Daniel|last9=Söylemezoglu|first9=Figen|date=2020-01|title=Isomorphic diffuse glioma is a morphologically and molecularly distinct tumour entity with recurrent gene fusions of MYBL1 or MYB and a benign disease course|url=https://pubmed.ncbi.nlm.nih.gov/31563982|journal=Acta Neuropathologica|volume=139|issue=1|pages=193–209|doi=10.1007/s00401-019-02078-w|issn=1432-0533|pmc=7477753|pmid=31563982}}</ref><ref>{{Cite journal|last=Chiang|first=Jason|last2=Harreld|first2=Julie H.|last3=Tinkle|first3=Christopher L.|last4=Moreira|first4=Daniel C.|last5=Li|first5=Xiaoyu|last6=Acharya|first6=Sahaja|last7=Qaddoumi|first7=Ibrahim|last8=Ellison|first8=David W.|date=2019-12|title=A single-center study of the clinicopathologic correlates of gliomas with a MYB or MYBL1 alteration|url=https://pubmed.ncbi.nlm.nih.gov/31595312|journal=Acta Neuropathologica|volume=138|issue=6|pages=1091–1092|doi=10.1007/s00401-019-02081-1|issn=1432-0533|pmc=7467132|pmid=31595312}}</ref>. These adult diffuse gliomas exhibit alterations of ''MYBL1'' rather than ''MYB''. Gene fusions with multiple partners characterize the pediatric ''MYB'' or ''MYBL1-''altered gliomas<ref>{{Cite journal|last=Ramkissoon|first=Lori A.|last2=Horowitz|first2=Peleg M.|last3=Craig|first3=Justin M.|last4=Ramkissoon|first4=Shakti H.|last5=Rich|first5=Benjamin E.|last6=Schumacher|first6=Steven E.|last7=McKenna|first7=Aaron|last8=Lawrence|first8=Michael S.|last9=Bergthold|first9=Guillaume|date=2013-05-14|title=Genomic analysis of diffuse pediatric low-grade gliomas identifies recurrent oncogenic truncating rearrangements in the transcription factor MYBL1|url=https://pubmed.ncbi.nlm.nih.gov/23633565|journal=Proceedings of the National Academy of Sciences of the United States of America|volume=110|issue=20|pages=8188–8193|doi=10.1073/pnas.1300252110|issn=1091-6490|pmc=3657784|pmid=23633565}}</ref><ref>{{Cite journal|last=Barinfeld|first=Orit|last2=Zahavi|first2=Alon|last3=Weiss|first3=Shirel|last4=Toledano|first4=Helen|last5=Michowiz|first5=Shalom|last6=Goldenberg-Cohen|first6=Nitza|date=2022|title=Genetic Alteration Analysis of IDH1, IDH2, CDKN2A, MYB and MYBL1 in Pediatric Low-Grade Gliomas|url=https://pubmed.ncbi.nlm.nih.gov/35574540|journal=Frontiers in Surgery|volume=9|pages=880048|doi=10.3389/fsurg.2022.880048|issn=2296-875X|pmc=9096721|pmid=35574540}}</ref>. The most frequently identified fusion is with ''QKI''<ref>{{Cite journal|last=Suh|first=Ye Yoon|last2=Lee|first2=Kwanghoon|last3=Shim|first3=Yu-Mi|last4=Phi|first4=Ji Hoon|last5=Park|first5=Chul-Kee|last6=Kim|first6=Seung-Ki|last7=Choi|first7=Seung Hong|last8=Yun|first8=Hongseok|last9=Park|first9=Sung-Hye|date=2023-02-21|title=MYB/MYBL1::QKI fusion-positive diffuse glioma|url=https://pubmed.ncbi.nlm.nih.gov/36592415|journal=Journal of Neuropathology and Experimental Neurology|volume=82|issue=3|pages=250–260|doi=10.1093/jnen/nlac123|issn=1554-6578|pmc=9941827|pmid=36592415}}</ref><ref>{{Cite journal|last=Jain|first=Payal|last2=Resnick|first2=Adam C.|date=2017-03-04|title=MYB-QKI drives childhood brain tumors via tripartite mechanism|url=https://pubmed.ncbi.nlm.nih.gov/27973981|journal=Cell Cycle (Georgetown, Tex.)|volume=16|issue=5|pages=390–391|doi=10.1080/15384101.2016.1260990|issn=1551-4005|pmc=5351923|pmid=27973981}}</ref>''.'' The ''MYB'' or ''MYBL1-''altered diffuse gliomas in both children and adults are generally indolent and behave in a WHO grade 1 fashion.
The <u>clinical features</u> of this disease are detailed below:
* Medically refractory epilepsy since childhood.
* Signs and symptoms - History of epilepsy or seizure; Magnetic resonance imaging (MRI): well-delineated, occasionally infiltrative-appearing, non-enhancing T1-hypointense, T2-fluid attenuated inversion recovery-hyperintense lesion without restricted diffusion<ref>{{Cite journal|last=Fabbri|first=Viscardo Paolo|last2=Caporalini|first2=Chiara|last3=Asioli|first3=Sofia|last4=Buccoliero|first4=Annamaria|date=2022-12|title=Paediatric-type diffuse low-grade gliomas: a clinically and biologically distinct group of tumours with a favourable outcome|url=https://pubmed.ncbi.nlm.nih.gov/36534420|journal=Pathologica|volume=114|issue=6|pages=410–421|doi=10.32074/1591-951X-828|issn=1591-951X|pmc=9763978|pmid=36534420}}</ref>
* Laboratory findings - Genetics: Negative for ''IDH1'' p.R132H, ''BRAF'' p.V600E; positive for ''MYBL1'' or ''MYB'' rearrangement, amplification, or copy number change
The <u>sites of involvement</u> of this disease are detailed below:
* Supratentorial (adult), cortical and subcortical regions of the cerebral cortex (pediatric)<ref>{{Cite journal|last=Fabbri|first=Viscardo Paolo|last2=Caporalini|first2=Chiara|last3=Asioli|first3=Sofia|last4=Buccoliero|first4=Annamaria|date=2022-12|title=Paediatric-type diffuse low-grade gliomas: a clinically and biologically distinct group of tumours with a favourable outcome|url=https://pubmed.ncbi.nlm.nih.gov/36534420|journal=Pathologica|volume=114|issue=6|pages=410–421|doi=10.32074/1591-951X-828|issn=1591-951X|pmc=9763978|pmid=36534420}}</ref>
The <u>morphologic features</u> of this disease are detailed below:
* Histomorphology: minimally to moderately hypercellular tumor; diffuse infiltration by monomorphic cells with ovoid to elongated nuclei, scant cytoplasm, fibrillary background<ref>{{Cite journal|last=Fabbri|first=Viscardo Paolo|last2=Caporalini|first2=Chiara|last3=Asioli|first3=Sofia|last4=Buccoliero|first4=Annamaria|date=2022-12|title=Paediatric-type diffuse low-grade gliomas: a clinically and biologically distinct group of tumours with a favourable outcome|url=https://pubmed.ncbi.nlm.nih.gov/36534420|journal=Pathologica|volume=114|issue=6|pages=410–421|doi=10.32074/1591-951X-828|issn=1591-951X|pmc=9763978|pmid=36534420}}</ref><ref>{{Cite journal|last=Suh|first=Ye Yoon|last2=Lee|first2=Kwanghoon|last3=Shim|first3=Yu-Mi|last4=Phi|first4=Ji Hoon|last5=Park|first5=Chul-Kee|last6=Kim|first6=Seung-Ki|last7=Choi|first7=Seung Hong|last8=Yun|first8=Hongseok|last9=Park|first9=Sung-Hye|date=2023-02-21|title=MYB/MYBL1::QKI fusion-positive diffuse glioma|url=https://pubmed.ncbi.nlm.nih.gov/36592415|journal=Journal of Neuropathology and Experimental Neurology|volume=82|issue=3|pages=250–260|doi=10.1093/jnen/nlac123|issn=1554-6578|pmc=9941827|pmid=36592415}}</ref>
The <u>immunophenotype</u> of this disease is detailed below:
* Positivity for GFAP, below 1% Ki-67 index, negative for OLIG2 and IDH1 R132H<ref>{{Cite journal|last=Wefers|first=Annika K.|last2=Stichel|first2=Damian|last3=Schrimpf|first3=Daniel|last4=Coras|first4=Roland|last5=Pages|first5=Mélanie|last6=Tauziède-Espariat|first6=Arnault|last7=Varlet|first7=Pascale|last8=Schwarz|first8=Daniel|last9=Söylemezoglu|first9=Figen|date=2020-01|title=Isomorphic diffuse glioma is a morphologically and molecularly distinct tumour entity with recurrent gene fusions of MYBL1 or MYB and a benign disease course|url=https://pubmed.ncbi.nlm.nih.gov/31563982|journal=Acta Neuropathologica|volume=139|issue=1|pages=193–209|doi=10.1007/s00401-019-02078-w|issn=1432-0533|pmc=7477753|pmid=31563982}}</ref>
* Positive (universal) - GFAP
* Positive (subset) - Ki-67 index below 1%
* Negative (universal) - OLIG2, IDH1 R132H
==Links==
None


==References==
==References==
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