Astrocytoma - Revision history

Jensflorian: /* Uncommon Astrocytomas */ link

2022-10-17T13:48:17Z

Uncommon Astrocytomas: link

← Older revision		Revision as of 13:48, 17 October 2022
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	* Usu. MAPK-pathway alterations + CDKN2A homozygous deletion.		* Usu. MAPK-pathway alterations + CDKN2A homozygous deletion.
	* Distinct methylation profile.		* Distinct methylation profile.
	* Depreceated terminology: Anaplastic pilocytic astrocytoma.		{{Main\|High-grade astrocytoma with piloid features}}

	==Gliomatosis cerebri==		==Gliomatosis cerebri==

Jensflorian: /* Uncommon Astrocytomas */ HGAP

2022-10-17T13:42:43Z

Uncommon Astrocytomas: HGAP

← Older revision		Revision as of 13:42, 17 October 2022
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	{{Main\|Diffuse hemispheric glioma, H3 G34-mutant}}		{{Main\|Diffuse hemispheric glioma, H3 G34-mutant}}

			==High-grade astrocytoma with piloid features==
			* Frequent in posterior fossa (75%).
			* 1-3% of all brain tumors.
			* Histology may resemble Glionblastoma or Pleomorphic xanthoastrocytoma.
			* Tumor is enriched for piloid cell processes.
			* ATRX nuclear loss is frequent.
			* Usu. MAPK-pathway alterations + CDKN2A homozygous deletion.
			* Distinct methylation profile.
			* Depreceated terminology: Anaplastic pilocytic astrocytoma.

	==Gliomatosis cerebri==		==Gliomatosis cerebri==

Jensflorian: diffuse vs. adult category

2022-10-17T13:36:11Z

diffuse vs. adult category

← Older revision		Revision as of 13:36, 17 October 2022
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	*[[Astrocytoma, IDH-mutant]].		*[[Astrocytoma, IDH-mutant]].
	*[[Glioblastoma]], IDH wildtype.		*[[Glioblastoma]], IDH wildtype.
	*High-grade astrocytoma with piloid features.		*[[High-grade astrocytoma with piloid features]].
	*[[Pleomorphic xanthroastrocytoma]].		*[[Pleomorphic xanthroastrocytoma]].
	*[[Subependymal giant cell astrocytoma]].		*[[Subependymal giant cell astrocytoma]].
	*[[Chordoid glioma]].		*Chordoid glioma.

	=Pediatric-type astrocytomas=		=Pediatric-type astrocytomas=
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	*[[Pediatric-type diffuse high-grade glioma]].		*[[Pediatric-type diffuse high-grade glioma]].
	*[[Pediatric-type diffuse low-grade glioma]].		*[[Pediatric-type diffuse low-grade glioma]].
	*[[Astroblastoma]].		*[[Astroblastoma]], MN1-altered.

			=Diffuse growing astrocytomas=
			*[[Astrocytoma, IDH-mutant]].
			*[[Glioblastoma]], IDH wildtype.
			*[[Diffuse midline glioma, H3 K27-altered]].
			*[[Diffuse hemispheric glioma, H3 G34-mutant]].
			*[[Diffuse astrocytoma, MYB- or MYBL-altered]].
			*Diffuse pediatric-type high-grade glioma, H3-wildtype and IDH-wildtype.
			*Angiocentric glioma.
			*Diffuse low-grade glioma, MAPK pathway-altered.

			=Circumscribed astrocytomas=
			*[[Pilocytic astrocytoma]].
			*[[High-grade astrocytoma with piloid features]].
			*[[Pleomorphic xanthroastrocytoma]].
			*[[Subependymal giant cell astrocytoma]].
			*[[Chordoid glioma]].
			*[[Astroblastoma]], MN1-altered.

	=Common Astrocytomas=		=Common Astrocytomas=

Jensflorian: fix link

2022-04-13T11:28:33Z

fix link

← Older revision		Revision as of 11:28, 13 April 2022
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	* Astrocytoma, IDH mutant are less common than glioblastoma.		* Astrocytoma, IDH mutant are less common than glioblastoma.
	* Grade 2-4 depends on histological and molecular criteria:		* Grade 2-4 depends on histological and molecular criteria:
	{{Main\|Astrocytoma, IDH mutant}}		{{Main\|Astrocytoma, IDH-mutant}}

	=== Astrocytoma, IDH mutant grade 2===		=== Astrocytoma, IDH mutant grade 2===

Jensflorian: link

2022-04-13T11:26:59Z

link

← Older revision		Revision as of 11:26, 13 April 2022
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	* Astrocytoma, IDH mutant are less common than glioblastoma.		* Astrocytoma, IDH mutant are less common than glioblastoma.
	* Grade 2-4 depends on histological and molecular criteria:		* Grade 2-4 depends on histological and molecular criteria:
			{{Main\|Astrocytoma, IDH mutant}}

	=== Astrocytoma, IDH mutant grade 2===		=== Astrocytoma, IDH mutant grade 2===
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	* Typically seen in adults.		* Typically seen in adults.
	* Usually shows progression to astrocytoma IDH mutant, grade 4.		* Usually shows progression to astrocytoma IDH mutant, grade 4.
	~~{{Main\|Diffuse astrocytoma}}~~

	===Astrocytoma, IDH mutant grade 3===		===Astrocytoma, IDH mutant grade 3===
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	* Increased cellularity, cell atypia and mitotic activity.		* Increased cellularity, cell atypia and mitotic activity.
	* Lacks endothelial proliferations and necrosis of glioblastoma.		* Lacks endothelial proliferations and necrosis of glioblastoma.
	~~{{Main\|Anaplastic astrocytoma}}~~

	===Astrocytoma, IDH mutant grade 4===		===Astrocytoma, IDH mutant grade 4===

Jensflorian: Update on categories

2022-04-06T12:05:39Z

Update on categories

← Older revision		Revision as of 12:05, 6 April 2022
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	An '''astrocytoma''' is a neoplasm derived from an [[neurohistology\|astrocyte]]. Astrocytomas are common glial tumours and grouped together with [[Oligodendroglioma]] and glioneuronal tumours in the current WHO brain tumor classficiation. Some (often circumscribed) astrocytic tumors and pediatric tumours are biologically different from adult-onset diffuse astrocytomas. An overview of CNS tumours is found in the ''[[CNS tumours]]'' article.		An '''astrocytoma''' is a neoplasm thought to be derived from an [[neurohistology\|astrocyte]]. Astrocytomas/Glioblastomas are most common type of glial tumours and grouped together with [[Oligodendroglioma]] and glioneuronal tumours in the current WHO brain tumor classficiation. Some (often circumscribed) astrocytic tumors and pediatric tumours are biologically different from adult-onset diffuse astrocytomas. An overview of other CNS tumours is found in the ''[[CNS tumours]]'' article.

	=Categorization=		=Categorization=
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	* Adult vs. pediatric tumours.		* Adult vs. pediatric tumours.
	* Circumscribed vs. diffusely growing astrocytomas.		* Circumscribed vs. diffusely growing astrocytomas.

			Until 2016 WHO classification, roman numerals I-IV were used for grading. The current 2021 WHO classification uses arabic numbering 1-4 for CNS WHO grading instead.

	=Overview=		=Overview=
	~~Until 2016 WHO classification, roman numerals I-IV were used for grading. The current 2021 WHO classification uses arabic numbering 1-4 for CNS WHO grading instead.~~		These astrocytic tumors are frequently diagnosed in neuropathology practice:
	{\| class="wikitable sortable"		{\| class="wikitable sortable"
	! Name		! Name
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	\| [[File:SEGA_HE.jpg\|thumb\|center\|150px]]		\| [[File:SEGA_HE.jpg\|thumb\|center\|150px]]
	\|}		\|}

			=Adult-type astrocytomas=
			*[[Astrocytoma, IDH-mutant]].
			*[[Glioblastoma]], IDH wildtype.
			*High-grade astrocytoma with piloid features.
			*[[Pleomorphic xanthroastrocytoma]].
			*[[Subependymal giant cell astrocytoma]].
			*[[Chordoid glioma]].

			=Pediatric-type astrocytomas=
			*[[Pilocytic astrocytoma]].
			*[[Pediatric-type diffuse high-grade glioma]].
			*[[Pediatric-type diffuse low-grade glioma]].
			*[[Astroblastoma]].

	=Common Astrocytomas=		=Common Astrocytomas=
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	* Large lipidized cells mimicking a malignant tumor		* Large lipidized cells mimicking a malignant tumor
	{{Main\|Pleomorphic xanthoastrocytoma}}		{{Main\|Pleomorphic xanthoastrocytoma}}

	~~==Gliomatosis cerebri==~~
	* Depreceated entity.
	* Was used for extensively diffusely growing astrocytic neoplasms.
	**Introduced in 1938 as a post-mortem diagnosis.<ref>SAMUEL NEVIN - GLIOMATOSIS CEREBRI, DOI: http://dx.doi.org/10.1093/brain/61.2.170 170-191 First published online: 1 June 1938</ref>
	**Since 2016 it is no longer considered a distinct entity.<ref>{{Cite journal \| last1 = Johnson \| first1 = DR. \| last2 = Guerin \| first2 = JB. \| last3 = Giannini \| first3 = C. \| last4 = Morris \| first4 = JM. \| last5 = Eckel \| first5 = LJ. \| last6 = Kaufmann \| first6 = TJ. \| title = 2016 Updates to the WHO Brain Tumor Classification System: What the Radiologist Needs to Know. \| journal = Radiographics \| volume = 37 \| issue = 7 \| pages = 2164-2180 \| month = \| year = \| doi = 10.1148/rg.2017170037 \| PMID = 29028423 }}</ref><ref>{{Cite journal \| last1 = Herrlinger \| first1 = U. \| last2 = Jones \| first2 = DT. \| last3 = Glas \| first3 = M. \| last4 = Hattingen \| first4 = E. \| last5 = Gramatzki \| first5 = D. \| last6 = Stuplich \| first6 = M. \| last7 = Felsberg \| first7 = J. \| last8 = Bähr \| first8 = O. \| last9 = Gielen \| first9 = GH. \| title = Gliomatosis cerebri: no evidence for a separate brain tumor entity. \| journal = Acta Neuropathol \| volume = \| issue = \| pages = \| month = Oct \| year = 2015 \| doi = 10.1007/s00401-015-1495-z \| PMID = 26493382 }}</ref>
	* More than 3 lobes have to be involved, us. bilateral (radiology required).
	* biologic behaviour corresponds to WHO III (ICD-O: 9381/3)
	* Based on presence / absence of a solid component authors propose two types:<ref>{{Cite journal \| last1 = Seiz \| first1 = M. \| last2 = Tuettenberg \| first2 = J. \| last3 = Meyer \| first3 = J. \| last4 = Essig \| first4 = M. \| last5 = Schmieder \| first5 = K. \| last6 = Mawrin \| first6 = C. \| last7 = von Deimling \| first7 = A. \| last8 = Hartmann \| first8 = C. \| title = Detection of IDH1 mutations in gliomatosis cerebri, but only in tumors with additional solid component: evidence for molecular subtypes. \| journal = Acta Neuropathol \| volume = 120 \| issue = 2 \| pages = 261-7 \| month = Aug \| year = 2010 \| doi = 10.1007/s00401-010-0701-2 \| PMID = 20514489 }}</ref>
	** GC type 1: classic diffuse growth, without IDH1/2 mutation.
	** GC type 2: with a solid portion, mostly IDH1 mutant.
	* Genetic studies indicate strong overlap with diffuse astrocytic gliomas, oligodendrogliomas and glioblastoma.

	==Diffuse midline glioma, H3 K27-altered==		==Diffuse midline glioma, H3 K27-altered==
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	* H3F3A missense mutation G34R or G34V.		* H3F3A missense mutation G34R or G34V.
	{{Main\|Diffuse hemispheric glioma, H3 G34-mutant}}		{{Main\|Diffuse hemispheric glioma, H3 G34-mutant}}


			==Gliomatosis cerebri==
			* Depreceated entity.
			* Was used for extensively diffusely growing astrocytic neoplasms.
			**Introduced in 1938 as a post-mortem diagnosis.<ref>SAMUEL NEVIN - GLIOMATOSIS CEREBRI, DOI: http://dx.doi.org/10.1093/brain/61.2.170 170-191 First published online: 1 June 1938</ref>
			**Since 2016 it is no longer considered a distinct entity.<ref>{{Cite journal \| last1 = Johnson \| first1 = DR. \| last2 = Guerin \| first2 = JB. \| last3 = Giannini \| first3 = C. \| last4 = Morris \| first4 = JM. \| last5 = Eckel \| first5 = LJ. \| last6 = Kaufmann \| first6 = TJ. \| title = 2016 Updates to the WHO Brain Tumor Classification System: What the Radiologist Needs to Know. \| journal = Radiographics \| volume = 37 \| issue = 7 \| pages = 2164-2180 \| month = \| year = \| doi = 10.1148/rg.2017170037 \| PMID = 29028423 }}</ref><ref>{{Cite journal \| last1 = Herrlinger \| first1 = U. \| last2 = Jones \| first2 = DT. \| last3 = Glas \| first3 = M. \| last4 = Hattingen \| first4 = E. \| last5 = Gramatzki \| first5 = D. \| last6 = Stuplich \| first6 = M. \| last7 = Felsberg \| first7 = J. \| last8 = Bähr \| first8 = O. \| last9 = Gielen \| first9 = GH. \| title = Gliomatosis cerebri: no evidence for a separate brain tumor entity. \| journal = Acta Neuropathol \| volume = \| issue = \| pages = \| month = Oct \| year = 2015 \| doi = 10.1007/s00401-015-1495-z \| PMID = 26493382 }}</ref>
			* More than 3 lobes have to be involved, us. bilateral (radiology required).
			* biologic behaviour corresponds to WHO III (ICD-O: 9381/3)
			* Based on presence / absence of a solid component authors propose two types:<ref>{{Cite journal \| last1 = Seiz \| first1 = M. \| last2 = Tuettenberg \| first2 = J. \| last3 = Meyer \| first3 = J. \| last4 = Essig \| first4 = M. \| last5 = Schmieder \| first5 = K. \| last6 = Mawrin \| first6 = C. \| last7 = von Deimling \| first7 = A. \| last8 = Hartmann \| first8 = C. \| title = Detection of IDH1 mutations in gliomatosis cerebri, but only in tumors with additional solid component: evidence for molecular subtypes. \| journal = Acta Neuropathol \| volume = 120 \| issue = 2 \| pages = 261-7 \| month = Aug \| year = 2010 \| doi = 10.1007/s00401-010-0701-2 \| PMID = 20514489 }}</ref>
			** GC type 1: classic diffuse growth, without IDH1/2 mutation.
			** GC type 2: with a solid portion, mostly IDH1 mutant.
			* Genetic studies indicate strong overlap with diffuse astrocytic gliomas, oligodendrogliomas and glioblastoma.

	==Gliosarcoma==		==Gliosarcoma==

Jensflorian: Categorization

2022-04-06T11:50:04Z

Categorization

← Older revision		Revision as of 11:50, 6 April 2022
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	An '''astrocytoma''' is a neoplasm derived from an [[neurohistology\|astrocyte]]. ~~Diffuse astrocytomas~~ are common glial tumours and grouped together with [[Oligodendroglioma]] and glioneuronal tumours in the current WHO brain tumor classficiation. Some (often circumscribed) astrocytic tumors and pediatric tumours are biologically different from adult-onset diffuse astrocytomas. An overview of CNS tumours is found in the ''[[CNS tumours]]'' article.		An '''astrocytoma''' is a neoplasm derived from an [[neurohistology\|astrocyte]]. Astrocytomas are common glial tumours and grouped together with [[Oligodendroglioma]] and glioneuronal tumours in the current WHO brain tumor classficiation. Some (often circumscribed) astrocytic tumors and pediatric tumours are biologically different from adult-onset diffuse astrocytomas. An overview of CNS tumours is found in the ''[[CNS tumours]]'' article.

			=Categorization=
			Astrocytomas can be categorized in serveral ways.
			* Common vs. uncommon tumours.
			* Adult vs. pediatric tumours.
			* Circumscribed vs. diffusely growing astrocytomas.

	=Overview=		=Overview=
	Until 2016 WHO classification, roman numerals I-IV were used for grading. The ~~upcoming~~ 2021 WHO classification ~~will use~~ arabic numbering 1-4 instead.		Until 2016 WHO classification, roman numerals I-IV were used for grading. The current 2021 WHO classification uses arabic numbering 1-4 for CNS WHO grading instead.
	{\| class="wikitable sortable"		{\| class="wikitable sortable"
	! Name		! Name
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	\|}		\|}

	=Common=		=Common Astrocytomas=
	==Pilocytic astrocytoma==		==Pilocytic astrocytoma==
	* Benign, cystic, infratentorial.		* Benign, cystic, infratentorial.
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	{{Main\|Glioblastoma}}		{{Main\|Glioblastoma}}

	=Uncommon=		=Uncommon Astrocytomas=
	==Diffuse astrocytoma, MYB- or MYBL-altered==		==Diffuse astrocytoma, MYB- or MYBL-altered==
	* Pediatric-type diffuse low-grade glioma.		* Pediatric-type diffuse low-grade glioma.

Jensflorian: moved Diffuse midline glioma, H3 K27-altered to its new category

2022-04-04T09:10:05Z

moved Diffuse midline glioma, H3 K27-altered to its new category

← Older revision		Revision as of 09:10, 4 April 2022
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	* Mostly in children and adolescents.		* Mostly in children and adolescents.
	* Includes diffuse intrinsic pontine gliomas (DPIG).		* Includes diffuse intrinsic pontine gliomas (DPIG).
	* Newly defined entity since WHO 2016 classification.<ref>{{Cite journal \| last1 = Louis \| first1 = DN. \| last2 = Perry \| first2 = A. \| last3 = Reifenberger \| first3 = G. \| last4 = von Deimling \| first4 = A. \| last5 = Figarella-Branger \| first5 = D. \| last6 = Cavenee \| first6 = WK. \| last7 = Ohgaki \| first7 = H. \| last8 = Wiestler \| first8 = OD. \| last9 = Kleihues \| first9 = P. \| title = The 2016 World Health Organization Classification of Tumors of the Central Nervous System: a summary. \| journal = Acta Neuropathol \| volume = 131 \| issue = 6 \| pages = 803-20 \| month = Jun \| year = 2016 \| doi = 10.1007/s00401-016-1545-1 \| PMID = 27157931 }}</ref>
	* Distinct biological and clinical group with poor prognosis.<ref>{{Cite journal \| last1 = Khuong-Quang \| first1 = DA. \| last2 = Buczkowicz \| first2 = P. \| last3 = Rakopoulos \| first3 = P. \| last4 = Liu \| first4 = XY. \| last5 = Fontebasso \| first5 = AM. \| last6 = Bouffet \| first6 = E. \| last7 = Bartels \| first7 = U. \| last8 = Albrecht \| first8 = S. \| last9 = Schwartzentruber \| first9 = J. \| title = K27M mutation in histone H3.3 defines clinically and biologically distinct subgroups of pediatric diffuse intrinsic pontine gliomas. \| journal = Acta Neuropathol \| volume = 124 \| issue = 3 \| pages = 439-47 \| month = Sep \| year = 2012 \| doi = 10.1007/s00401-012-0998-0 \| PMID = 22661320 }}</ref>
	** EGFR amplification is usu. absent.<ref>{{Cite journal \| last1 = Meyronet \| first1 = D. \| last2 = Esteban-Mader \| first2 = M. \| last3 = Bonnet \| first3 = C. \| last4 = Joly \| first4 = MO. \| last5 = Uro-Coste \| first5 = E. \| last6 = Amiel-Benouaich \| first6 = A. \| last7 = Forest \| first7 = F. \| last8 = Rousselot-Denis \| first8 = C. \| last9 = Burel-Vandenbos \| first9 = F. \| title = Characteristics of H3 K27M-mutant gliomas in adults. \| journal = Neuro Oncol \| volume = 19 \| issue = 8 \| pages = 1127-1134 \| month = Aug \| year = 2017 \| doi = 10.1093/neuonc/now274 \| PMID = 28201752 }}</ref>
	** Tumors usu. have unmethylated MGMT promotor.<ref>{{Cite journal \| last1 = Banan \| first1 = R. \| last2 = Christians \| first2 = A. \| last3 = Bartels \| first3 = S. \| last4 = Lehmann \| first4 = U. \| last5 = Hartmann \| first5 = C. \| title = Absence of MGMT promoter methylation in diffuse midline glioma, H3 K27M-mutant. \| journal = Acta Neuropathol Commun \| volume = 5 \| issue = 1 \| pages = 98 \| month = 12 \| year = 2017 \| doi = 10.1186/s40478-017-0500-2 \| PMID = 29246238 }}</ref>
	* MRI: May be or be not enhancing.
	*Histologic spectrum ranges from minimal hypercellularity to full-blown glioblastoma.

	~~Note: Cases may also appear outside midline structures and in adult patients.<ref>~~{{~~Cite journal~~ \| last1 = Nakata \| first1 = S. \| last2 = Nobusawa \| first2 = S. \| last3 = Yamazaki \| first3 = T. \| last4 = Osawa \| first4 = T. \| last5 = Horiguchi \| first5 = K. \| last6 = Hashiba \| first6 = Y. \| last7 = Yaoita \| first7 = H. \| last8 = Matsumura \| first8 = N. \| last9 = Ikota \| first9 = H. \| title = Histone H3 ~~K27M mutations in adult cerebellar high-grade gliomas. \| journal = Brain Tumor Pathol \| volume = 34 \| issue = 3 \| pages = 113~~-~~119 \| month = Jul \| year = 2017 \| doi = 10.1007/s10014-017-0288-6 \| PMID = 28547652~~ }}~~</ref>~~		{{Main\|Diffuse midline glioma, H3 K27-altered}}

	~~<gallery>~~
	~~File:K27M mutant diffuse glioma of the midline.jpg\|Nuclear [[H3F3A]] K27M immunostaining in a diffuse glioma of the midline. (WC/jensflorian)~~
	~~</gallery>~~

	==Diffuse hemispheric glioma, H3 G34-mutant==		==Diffuse hemispheric glioma, H3 G34-mutant==

Jensflorian: Category update

2022-04-04T08:04:59Z

Category update

← Older revision		Revision as of 08:04, 4 April 2022
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	An '''astrocytoma''' is a neoplasm derived from an [[neurohistology\|astrocyte]]. Diffuse astrocytomas are common glial tumours and grouped together with [[Oligodendroglioma]] in the current WHO brain tumor classficiation. Some (often circumscribed) astrocytic tumors are biologically different from diffuse astrocytomas An overview of CNS tumours is found in the ''[[CNS tumours]]'' article.		An '''astrocytoma''' is a neoplasm derived from an [[neurohistology\|astrocyte]]. Diffuse astrocytomas are common glial tumours and grouped together with [[Oligodendroglioma]] and glioneuronal tumours in the current WHO brain tumor classficiation. Some (often circumscribed) astrocytic tumors and pediatric tumours are biologically different from adult-onset diffuse astrocytomas. An overview of CNS tumours is found in the ''[[CNS tumours]]'' article.

	=Overview=		=Overview=

Jensflorian: /* Uncommon */ + Diffuse hemispheric glioma, H3 G34-mutant

2022-04-04T08:01:47Z

Uncommon: + Diffuse hemispheric glioma, H3 G34-mutant

← Older revision		Revision as of 08:01, 4 April 2022
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	* Genetic studies indicate strong overlap with diffuse astrocytic gliomas, oligodendrogliomas and glioblastoma.		* Genetic studies indicate strong overlap with diffuse astrocytic gliomas, oligodendrogliomas and glioblastoma.

	==Diffuse midline glioma, H3 ~~K27M mutant~~==		==Diffuse midline glioma, H3 K27-altered==
	* High-grade astrocytic neoplasm associated with midline structures (thalamus, brain stem, spinal cord).		* High-grade astrocytic neoplasm associated with midline structures (thalamus, brain stem, spinal cord).
	* Mostly in children and adolescents.		* Mostly in children and adolescents.
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	File:K27M mutant diffuse glioma of the midline.jpg\|Nuclear [[H3F3A]] K27M immunostaining in a diffuse glioma of the midline. (WC/jensflorian)		File:K27M mutant diffuse glioma of the midline.jpg\|Nuclear [[H3F3A]] K27M immunostaining in a diffuse glioma of the midline. (WC/jensflorian)
	</gallery>		</gallery>

			==Diffuse hemispheric glioma, H3 G34-mutant==
			* Infiltrative hemispheric glioma of young adults.
			* Glioblastoma-like appearance (CNS WHO grade 4 tumor).
			* Newly defined entity in WHO 2021 classification.
			* H3F3A missense mutation G34R or G34V.
			{{Main\|Diffuse hemispheric glioma, H3 G34-mutant}}

	==Gliosarcoma==		==Gliosarcoma==