Difference between revisions of "Neuropathology tumours"

Jump to navigation Jump to search

Neuropathology tumours (view source)

Revision as of 09:04, 14 April 2022

11,865 bytes added ,  09:04, 14 April 2022
Minor rearrangement
(Minor rearrangement)
 
(312 intermediate revisions by 5 users not shown)
Line 1: Line 1:
[[Image:Gemistocytic Astrocytoma 003.jpg|thumb|right|A brain stem [[astrocytoma]]. (WC)]]
The article covers '''tumours in neuropathology'''.  Tumours are a large part of [[neuropathology]].  [[Cytopathology]] of CNS tumours is dealt with in the article ''[[CNS cytopathology]]''.
The article covers '''tumours in neuropathology'''.  Tumours are a large part of [[neuropathology]].  [[Cytopathology]] of CNS tumours is dealt with in the article ''[[CNS cytopathology]]''.


There is a separate article for '''[[peripheral nerve sheath tumours]]'''.
There are separate articles for ''[[peripheral nerve sheath tumours]]'' and ''[[pituitary gland|pituitary/peri-pituitary lesions]]''.


==Brain tumours==
==Brain tumours - overview==
===Adult===
===Alphabetical===
For overview see [[:Category:Neuropathology_tumours|here]]
 
===By age group===
====Adult====
Four most common types of brain tumours:<ref>[http://neurosurgery.mgh.harvard.edu/abta/primer.htm http://neurosurgery.mgh.harvard.edu/abta/primer.htm]</ref>
Four most common types of brain tumours:<ref>[http://neurosurgery.mgh.harvard.edu/abta/primer.htm http://neurosurgery.mgh.harvard.edu/abta/primer.htm]</ref>
# Metastatic brain tumours (barely edges out primary tumours)
# Metastatic brain tumours (barely edges out primary tumours)
#*Lung (most common),
#*[[Lung cancer|Lung]] (most common).
#*Breast,
#*[[Invasive breast cancer|Breast]].
#*Melanoma,
#*[[Melanoma]].
#*[[Renal cell carcinoma]] (RCC).
#*[[Renal cell carcinoma]] (RCC).
# Glioblastoma aka ''glioblastoma multiforme''.
# [[Glioblastoma]], IDH-wildtype.
# Anaplastic (malignant) astrocytoma.
# [[Astrocytoma, IDH-mutant]].
# Meningioma.
# [[Meningioma]].


===Children===
====Children====
# Astrocytoma.
# [[Pilocytic astrocytoma]].
# Medulloblastoma.
# [[Medulloblastoma]].
# Ependymoma.
# [[Ependymoma]].
# Pontine glioma, often [[Diffuse midline glioma, H3 K27-altered]].


===Location (most common)===
===By location===
Certain tumours like to hang-out at certain places:<ref>URL: [http://www.msdlatinamerica.com/ebooks/DiagnosticNeuropathologySmears/files/4ce563fb7e8e48fc9ed8b42e296a7747.gif http://www.msdlatinamerica.com/ebooks/DiagnosticNeuropathologySmears/files/4ce563fb7e8e48fc9ed8b42e296a7747.gif] and [http://www.msdlatinamerica.com/ebooks/DiagnosticNeuropathologySmears/sid117213.html http://www.msdlatinamerica.com/ebooks/DiagnosticNeuropathologySmears/sid117213.html]. Accessed on: 2 November 2010.</ref>
Certain tumours like to hang-out at certain places:<ref>URL: [http://www.msdlatinamerica.com/ebooks/DiagnosticNeuropathologySmears/files/4ce563fb7e8e48fc9ed8b42e296a7747.gif http://www.msdlatinamerica.com/ebooks/DiagnosticNeuropathologySmears/files/4ce563fb7e8e48fc9ed8b42e296a7747.gif] and [http://www.msdlatinamerica.com/ebooks/DiagnosticNeuropathologySmears/sid117213.html http://www.msdlatinamerica.com/ebooks/DiagnosticNeuropathologySmears/sid117213.html]. Accessed on: 2 November 2010.</ref>
*Cerebrum:
====Cerebrum====
**Cortical based - oligodendroglioma.
*Cortical based - [[oligodendroglioma]].
**Grey-white junction - metastases.
*Grey-white junction - metastases.
**White matter - astrocytoma, glioblastoma.
*White matter - astrocytoma, [[glioblastoma]].
**Periventricular - CNS lymphoma.
*Periventricular - CNS lymphoma.
**Cystic - ganglioglioma, pilocytic astrocytoma, pleomorphic xanthoastrocytoma.
*Cystic - [[ganglioglioma]], [[pilocytic astrocytoma]], [[pleomorphic xanthoastrocytoma]].
*Cerebellum:
====Cerebellum====
**Midline/central - medulloblastoma.
*Midline/central - [[medulloblastoma]].
**Cystic lesion - pilocytic astrocytoma (younger individual), hemangioblastoma (older individual).
*Cystic lesion - pilocytic astrocytoma (younger individual), [[hemangioblastoma]] (older individual).
**Solid lesion (older individual) - metastasis.
*Solid lesion (older individual) - [[metastasis]].
*Spinal cord:
====Sella turcica====
**Ependymoma, glioblastoma.
* [[Pituitary adenoma]].
**Filum terminale - myxopapillary ependymoma, paraganglioma.
* [[Craniopharyngioma]].
 
less common:
* [[Pituicytoma]].
* [[Granular cell tumour]].
* [[Germinoma]].
* [[Chordoma]]
* Rathke cleft cyst.
* Hypophysitis.
* Xanthogranuloma.
====Spinal cord====
*[[Ependymoma]]
*[[Glioblastoma]]
*[[Meningioma]]
*Carcinoma metastasis
*[[Hemangioblastoma]]
====Filum terminale====
====Filum terminale====
*Filum terminale = bottom end of the spinal cord - has a limited differential.
*[[Meningioma]].
 
*[[Myxopapillary ependymoma]].
DDx:<ref>JLK. 31 May 2010.</ref>
*[[Neurofibroma]].
*Meningioma.
*[[Schwannoma]].
*Myxopapillary ependymoma.
*[[Paraganglioma]].
*Neurofibroma.
====Meninges====
*Schwannoma.
* [[Meningioma]].
*Paraganglioma.
* [[Solitary fibrous tumour]] / Hemangiopericytoma.
 
* [[Hemangioblastoma]].
====Cerebellopontine angle====
less common:
DDx:<ref>R. Kiehl. 8 November 2010.</ref>
* [[Melanoma]] / Melanocytoma.
*Schwannoma.
* Lymphoproliferative diseases.
*Meningioma.
* [[Sarcoidosis]]
*Dermoid cyst/epidermoid cyst.
* [[Arachnoid cyst]].
*Ependymoma.
* Disseminated oligodendroglial-like leptomeningeal tumour.
*Choroid plexus papilloma.
* Desmoplastic infantile astrocytoma / ganglioglioma.
* Meningioangiomatosis.
* Calcifying pseudoneoplasm.  
====Skull====
* [[Fibrous dysplasia]].
* [[Paget disease]].
* [[Histiocytosis]].
* [[Hemangioma]].
* [[Aneurysmal bone cyst]].
* [[Plasma_cell_neoplasms#Multiple_myeloma|Multiple myeloma]].
====Skull base / Cerebellopontine angle====
* [[Schwannoma]].
* [[Meningioma]].
* [[Dermoid cyst]] / epidermoid cyst.
less common:
* [[Ependymoma]].
* [[Choroid plexus papilloma]].
* [[Glomus tumour]].
* [[Chordoma]].
* [[Chondrosarcoma]].
* [[Olfactory neuroblastoma]].
* [[Endolymphatic sac tumour]].


===Primary vs. secondary===
===Primary versus secondary===
Glial tumours:
*[[AKA]] (primary) brain tumour versus metastatic cancer.
====Primary====
[[Glioma|Glial tumours]]:
*Cytoplasmic processes - '''key feature'''.
*Cytoplasmic processes - '''key feature'''.
**Best seen at highest magnification - usu. ~1 micrometer.
**Best seen at highest magnification - usu. ~1 micrometer.
**Processes may branch.
**Processes may branch.
*Ill-defined border/blend with the surrounding brain/.
*Ill-defined border/blend with the surrounding brain.


==Astrocytomas==
[[Meningioma]]:
===Overview===
*Lesion often dura-based.
*Pilocytic astrocytomas (WHO Grade I).
*Mesenchymal tumor (often contains collagen).
*Dysembryoplastic neuroepithelial tumour (DNT), (WHO Grade I).
*Low-grade (diffuse) astrocytomas (Grade II).
*Anaplastic astrocytomas (Grade III).
*Glioblastoma (Grade IV).


===Microscopic===
[[Lymphoma]]:
Features:<ref name=pmid>{{cite journal |author=Rong Y, Durden DL, Van Meir EG, Brat DJ |title='Pseudopalisading' necrosis in glioblastoma: a familiar morphologic feature that links vascular pathology, hypoxia, and angiogenesis |journal=J. Neuropathol. Exp. Neurol. |volume=65 |issue=6 |pages=529–39 |year=2006 |month=June |pmid=16783163 |doi= |url=}}</ref><ref>[http://dictionary.reference.com/browse/palisading http://dictionary.reference.com/browse/palisading]</ref>
*Primary CNS Lymphoma (PCNSL) is usu. a diffuse large B-cell lymphoma.
*Glial processes - '''key feature'''.
*Large (lymphoid) cells, ergo usu. not a difficult diagnosis.
**Thin stringy cytoplasmic processes - best seen at high power in less cellular areas.
**~2x size of resting lymphocyte, nucleoli.
*Lesion predominantly perivascular.
 
====Secondary====
*Carcinomas:
**Well-demarcated border between brain and lesion - '''key feature'''.
**No cytoplasmic processes.
**Usu. have nuclear atypia of malignancy.
**Nuclei often ~3-4x the size of a [[RBC]].
**+/-Glandular arrangement.
**+/-Nucleoli.
*Melanoma.
*Secondary Lymphoma.
*Sarcomas (rare).


Images:
===By growth pattern===
*[http://moon.ouhsc.edu/kfung/jty1/opaq/PathQuiz/N0A002-PQ01-M.htm Endothelial proliferation in a GBM (ouhsc.edu)].
====Infiltrative astrocytomas====
*[http://moon.ouhsc.edu/kfung/jty1/neurotest/Q05-Ans.htm Endothelial proliferation (ouhse.edu)].
*[[Astrocytoma, IDH-mutant]].
*[[Glioblastoma]], IDH-wildtype.


Notes:
Notes:
*Glial vs. non-glial tumours:
**Glial: "blends into brain"/gradual transition to non-tumour brain.
**Glial: "blends into brain"/gradual transition to non-tumour brain.
**Non-glial: no glial processes.


====Grading====
====Non-infiltrative astrocytomas====
At least grade II:
**[[Pilocytic astrocytoma]]
*Nuclear pleomorphism.
**[[Pleomorphic xanthoastrocytoma]]
**[[Subependymal giant cell astrocytoma]].


At least grade III:
====Cystic tumours====
*Mitotic figures.  
DDx:<ref>URL: [http://path.upmc.edu/cases/case320/dx.html http://path.upmc.edu/cases/case320/dx.html]. Accessed on: 14 January 2012.</ref>
*[[Pilocytic astrocytoma]].
*[[Pleomorphic xanthoastrocytoma]].
*[[Ganglioglioma]].
*[[Hemangioblastoma]].
*[[Craniopharyngioma]].<ref>URL: [http://www.pathologyoutlines.com/Cnstumor.html#cystsgeneral http://www.pathologyoutlines.com/Cnstumor.html#cystsgeneral]. Accessed on: 14 January 2012.</ref>


At least grade IV:
*Microvascular proliferation ''or'' necrosis with pseudopalisading tumour cells.
**Pseudopalisading tumour cells = high tumour cell density adjacent to regions of necrosis; palisade = a fence of pales forming a defense barrier or fortification.


===Glioblastoma IHC===
Notes:
*GFAP - should stain cytoplasm of tumour cells and the perikaryon (nuclear membrane).
**Non-glial: no radiating glial processes.
*Ki-67 - usu. high >20% of cells.
*Rosenthal fibres within the tumour... often seen in [[pilocytic astrocytoma]].
*p53 - often +ve.
**Rosenthal fibres may be seen around a (very) slow growing tumour and represent a reactive process.
*IDH1 (isocitrate dehydrogenase 1).
*Inflammatory cells and macrophages should prompt consideration of an alternate diagnosis (e.g. [[cerebral infarct]], [[multiple sclerosis]]) - esp. if this is a primary lesion.<ref>URL: [http://path.upmc.edu/cases/case79/dx.html http://path.upmc.edu/cases/case79/dx.html]. Accessed on: 2 January 2012.</ref>
**+ve in tumours that arose from low-grade gliomas.<ref name=pmid19228619>{{cite journal |author=Yan H, Parsons DW, Jin G, ''et al.'' |title=IDH1 and IDH2 mutations in gliomas |journal=N. Engl. J. Med. |volume=360 |issue=8 |pages=765–73 |year=2009 |month=February |pmid=19228619 |pmc=2820383 |doi=10.1056/NEJMoa0808710 |url=}}</ref>
***Image: [http://en.wikipedia.org/wiki/File:IDH1_GBM_20x.jpg IDH1 +ve in glioblastoma (WP)].


Notes:
====Grading====
*IDH1 and IDH2 mutations - better survival.<ref name=pmid20975057>{{cite journal |author=Houillier C, Wang X, Kaloshi G, ''et al.'' |title=IDH1 or IDH2 mutations predict longer survival and response to temozolomide in low-grade gliomas |journal=Neurology |volume=75 |issue=17 |pages=1560–6 |year=2010 |month=October |pmid=20975057 |doi=10.1212/WNL.0b013e3181f96282 |url=}}</ref>
Nuclear pleomorphism present:
*At least grade II (diffuse astrocytoma).


==Pilocytic astrocytoma==
Mitotic figures present:
===General===
*At least grade III (anaplastic astrocytoma).
*Low-grade astrocytoma.
*Classically in the cerebellum in children; most common glioma in children.<ref name=Ref_PSNP82>{{Ref PSNP|82}}</ref>
*The ''optic glioma'' associated with neurofibromatosis 1.


===Gross===
Microvascular proliferation ''or'' necrosis with pseudopalisading tumour cells:
Features:<ref name=Ref_PSNP82>{{Ref PSNP|82}}</ref>
*Grade IV (glioblastoma [[AKA]] glioblastoma multiforme).
*Usually well-circumscribed.
*Cystic ''or'' solid.
*Do '''not''' smear. (Ref. ?)


===Microscopic===
Notes:
Features:<ref name=Ref_PSNP82-4>{{Ref PSNP|82-4}}</ref>
*Pseudopalisading tumour cells = high tumour cell density adjacent to regions of necrosis; palisade = a fence of poles forming a defensive barrier or fortification.
*Classically biphasic (though either may be absent):
*WHO Grading is currently based on expected biologiocal behaviour without treatment.
*#Fibrillar.
**Grading does not reflect molecular divergent groups within a tumor class  or response to therapy (Currently controversies in grading for IDH-mutant astrocytoma vs. IDH-wildtype astrocytoma).<ref>{{Cite journal  | last1 = Louis | first1 = DN. | last2 = von Deimling | first2 = A. | title = Grading of diffuse astrocytic gliomas: Broders, Kernohan, Zülch, the WHO… and Shakespeare. | journal = Acta Neuropathol | volume =  | issue =  | pages =  | month = Aug | year = 2017 | doi = 10.1007/s00401-017-1765-z | PMID = 28801693 }}</ref>
*#Microcystic/loose.
*Hair-like fibres ~ 1 micrometer; ''pilo-'' = hair.<ref>URL: [http://dictionary.reference.com/browse/pilo- http://dictionary.reference.com/browse/pilo-]. Accessed on: 24 November 2010.</ref>
**Best seen on smear or with GFAP [[IHC]].
*Rosenthal fibres - '''key feature'''.
**May be rare.  Not pathognomonic (see below).
*Eosinophilic granular bodies.
*Low cellularity - when compared to medulloblastoma and ependymoma.


Notes:
===By IHC===
*+/-Microvascular proliferation.
*GFAP - should stain cytoplasm of tumour cells and the perikaryon (nuclear membrane) of most [[Astrocytoma]]s.
*+/-Focal necrosis.
*[[IDH-1]](R132H) (isocitrate dehydrogenase 1) in [[Astrocytoma, IDH-mutant]].<ref name=pmid19228619>{{cite journal |author=Yan H, Parsons DW, Jin G, ''et al.'' |title=IDH1 and IDH2 mutations in gliomas |journal=N. Engl. J. Med. |volume=360 |issue=8 |pages=765–73 |year=2009 |month=February |pmid=19228619 |pmc=2820383 |doi=10.1056/NEJMoa0808710 |url=}}</ref><ref name=pmid20975057>{{cite journal |author=Houillier C, Wang X, Kaloshi G, ''et al.'' |title=IDH1 or IDH2 mutations predict longer survival and response to temozolomide in low-grade gliomas |journal=Neurology |volume=75 |issue=17 |pages=1560–6 |year=2010 |month=October |pmid=20975057 |doi=10.1212/WNL.0b013e3181f96282 |url=}}</ref>
**Necrosis with pseudopalisading more likely glioblastoma.
*[[H3F3A|H3F3A K27M]] in [[Diffuse midline glioma, H3 K27-altered]].  
*+/-Mitoses - not significant in the context of the Dx.
*[[ATRX]] -ve in [[Astrocytoma, IDH-mutant]] or [[Diffuse hemispheric glioma, H3 G34-mutant]].
*[[CD20]] in PCNSL.
*Cytokeratins in Carcinoma brain metastases, Plexus choroid tumours, [[AT/RT]], [[Papillary tumour of the pineal region]], [[Craniopharyngioma]].
*[[EMA]] in [[Meningioma]] and carcinoma brain metastases.
*PrgR in [[Meningioma]] and carcinoma metastases.
*[[Synaptophysin]] in glioneuronal tumours and Pituitary adenoma and embryonal tumours.


Images:  
===Common neuropathology tumours in a table===
*[http://commons.wikimedia.org/wiki/File:Rosenthal_HE_40x.jpg Rosenthal fibres (WC)].
{| class="wikitable"
*[http://moon.ouhsc.edu/kfung/jty1/neurotest/Q19-Ans.htm Rosenthal fibre (ouhsc.edu)].
|'''Type'''
|'''Key feature(s)'''
|'''Imaging'''
|'''History'''
|'''Notes'''
|'''IHC'''
|'''Images'''
|-
|Normal tissue
|cells regularly spaced, no nuc. atypia
|small lesion? / deep lesion?
|variable
|missed lesion?
|nil
|[[Image:Grey_matter_and_white_matter_-_very_high_mag.jpg |thumb|center|150px|Normal. (WC)]]
|-
|[[Reactive astrocytes]]
|astrocytes with well-demarcated eosinophilic cytoplasm, regular spacing, no nuc. atypia
|small lesion? / deep lesion?
|variable
|missed lesion / close to a lesion; non-specific pathologic process - need more tissue
|GFAP
|[[Image:Reactive_astrocytes_-_lfb_-_high_mag.jpg|thumb|center|150px|Reactive astrocytes. (WC)]]
|-
|[[Schwannoma]]
|cellular areas (Antoni A), paucicelluar areas (Antoni B), palisading of nuclei (Verocay bodies)
|extra-axial + intradural
|old or young
|need frozen section to Dx, DDx: [[meningioma]]
|S100, SOX10
|[[Image:Schwannoma_-_Antoni_A_and_B_-_very_high_mag.jpg|thumb|center|150px|Schwannoma. (WC)]]
|-
|[[Meningioma]]
|whorls, psammomatous calcs, nuclear inclusions
|extra-axial + intradural
|old or young
|may be diagnosed on smear, DDx: [[schwannoma]], choroid plexus
|EMA, PR, Ki-67
|[[Image:Meningioma_intermed_mag.jpg |thumb|center|150px|Meningioma. (WC)]]
|-
|[[Astrocytoma, IDH-mutant]] (CNS [[WHO]] grade 2 or grade 3)
|glial processes (esp. on smear), nuclear atypia (typical size var. ~3x, irreg. nuc. membrane, hyperchromasia), no Rosenthal fibres in the core of the lesion †, no microvascular proliferation, no necrosis
|often enhancing (suggests high grade), usu. supratentorial, usu. white matter
|usu. old, occ. young
|common
|IDH-1(R132H)+/-, GFAP+
| [[Image:Anaplastic_astrocytoma_-_very_high_mag_-_cropped.jpg | thumb| center| 150px|High-grade astrocytoma. (WC)]]
|-
|[[Glioblastoma]], IDH-wildtype (CNS [[WHO]] grade 4)
|glial processes (esp. on smear), nuclear atypia (typical size var. ~3x, irreg. nuc. membrane, hyperchromasia), no Rosenthal fibres in the core of the lesion †, microvascular proliferation or necrosis
|often enhancing (suggests high grade), usu. supratentorial, usu. white matter
|usu. old, occ. young
|very common, esp. glioblastoma
|IDH-1+/-, GFAP+
| [[Image:Glioblastoma (1).jpg | thumb| center| 150px|Glioblastoma. (WC)]]
|-
|[[Metastatic brain tumours|Metastasis]]
|sharp interface with brain, often glandular, +/-nucleoli, no glial processes
|often cerebellular, well-circumscribed
|usu. old
|often suspected to have metastatic disease
|[[TTF-1]], CK7, [[CK20]], BRST-2
|[[Image:Metastatic_adenocarcinoma_-_cerebellum_-_very_low_mag.jpg | thumb| center|150px |Metastasis. (WC)]]
|}
† Rosenthal fibres at the periphery of a lesion are a non-specific finding seen in chronic processes.


DDx (of Rosenthal fibers):<ref>MUN. 9 Mar 2009.</ref>
==Brain metastasis==
*Chronic reactive gliosis.
{{Main|Brain metastasis}}
*Subependymoma.
*Ganglioma.
*Alexander's disease (rare leukodystrophy).


DDx of pilocystic astrocytoma (brief):
*Piloid gliosis.
*Oligodendroglioma.
*Glioblastoma (uncommon - but important).


===IHC/special stains===
===Molecular===
Features:<ref name=Ref_PSNP84>{{Ref PSNP|84}}</ref>
See also: [[Molecular_pathology_tests#Neuropathology|Molecular Neuropathology]]
*GFAP +ve (fibres).
*PAS-D: eosinophilic granular bodies +ve.
*CD68: may have a significant macrophage component.
*KI-67: may be "high" (~20% ???).


===Grading===
==Gliomas==
*''WHO Grade I'' by definition.
{{Main|Glioma}}


==Pilomyxoid astrocytoma==
Gliomas, glioneuronal tumours and neuronal tumours are often categorized together.
===General===
Features:<ref name=Ref_PSNP86>{{Ref PSNP|86}}</ref>
*A variant of ''pilocytic astrocytoma''.
**Some have suggested it is a unique entity.<ref name=pmid16048293>{{cite journal |author=Komotar RJ, Mocco J, Jones JE, ''et al.'' |title=Pilomyxoid astrocytoma: diagnosis, prognosis, and management |journal=Neurosurg Focus |volume=18 |issue=6A |pages=E7 |year=2005 |month=June |pmid=16048293 |doi= |url=}}</ref>
*Childhood or adolescence.


===Gross===
===Astrocytic tumours===
Features:<ref name=Ref_PSNP86>{{Ref PSNP|86}}</ref>
{{Main|Astrocytoma}}
*Classically - hypothalamic location.
*Solid.
*Well-circumscribed.


===Microscopic===
* [[Astrocytoma]], IDH-mutant.
Features:<ref name=Ref_PSNP86>{{Ref PSNP|86}}</ref>
* [[Glioblastoma]], IDH-wildtype.
*Consists of small round/ovoid bland cells in a myxoid stroma.
** [[Gliosarcoma]] (a glioblastoma subtype)
*Hair-like fibres ~ 1 micrometer.
**Often difficult to appreciate on standard (H&E) histologic sections.
*Usually angiocentric (surround blood vessel) - '''key feature'''.


Notes:<ref name=Ref_PSNP86>{{Ref PSNP|86}}</ref>
Features:<ref name=pmid>{{cite journal |author=Rong Y, Durden DL, Van Meir EG, Brat DJ |title='Pseudopalisading' necrosis in glioblastoma: a familiar morphologic feature that links vascular pathology, hypoxia, and angiogenesis |journal=J. Neuropathol. Exp. Neurol. |volume=65 |issue=6 |pages=529–39 |year=2006 |month=June |pmid=16783163 |doi= |url=}}</ref><ref>[http://dictionary.reference.com/browse/palisading http://dictionary.reference.com/browse/palisading]</ref>
*Rosenthal fibres are absent - '''key negative'''.
*Glial processes - '''key feature'''.
*Monophasic (unlike classical pilocytic astrocytomas) - '''key negative'''.
**Thin stringy cytoplasmic processes - best seen at high power in less cellular areas.
*May rarely have eosinophilic granular bodies.
*No Rosenthal fibres within the tumour itself.


===Grading===
Images:
*''WHO Grade II'' by definition.<ref name=Ref_PSNP86>{{Ref PSNP|86}}</ref>
*[http://moon.ouhsc.edu/kfung/jty1/opaq/PathQuiz/N0A002-PQ01-M.htm Endothelial proliferation in a GBM (ouhsc.edu)].
*[http://moon.ouhsc.edu/kfung/jty1/neurotest/Q05-Ans.htm Endothelial proliferation (ouhse.edu)].
*[http://path.upmc.edu/cases/case368.html Gemistocytic astrocytoma - several images (upmc.edu)].


==Atypical teratoid/rhabdoid tumour==
Depreceated:
*Commonly abbreviated ''AT/RT''.
* Diffuse [[Astrocytoma]]
*May be written ''atypical teratoid rhabdoid tumour'', i.e. without the forward slash.
* [[Anaplastic astrocytoma]]
* [[Gliomatosis cerebri]]
* Spongioblastoma


===General===
===Oligodendroglial tumours===
*Usually supratentorial, occasionally in posterior fossa, case reports of spinal cord.
* [[Oligodendroglioma]], IDH-mutant and 1p/19q codeleted.


===Microscopic===
Depreceated:
Features:
* Anaplastic oligodendroglioma
*Cellular.
* [[Oligoastrocytoma]]
*Small round cells usu. with a prominent nucleolus.
* Anaplastic oligoastrocytoma
*Rhaboid cells.
**Cells with eosinophilic granular cytoplasm + eccentric nucleus. (???)
*Mitoses.


DDx:
===Pediatric-type diffuse high-grade glioma===
*Primitive neuroectodermal tumour (PNET).
{{Main|Pediatric-type diffuse high-grade glioma}}
*Diffuse astrocytoma.
* [[Astrocytoma#Diffuse_midline_glioma.2C_H3_K27M_mutant|Diffuse midline glioma H3 K27-mutant]]
*Choroid plexus carcinoma.
*Embryonal carcinoma.


===IHC===
===Pediatric-type diffuse low-grade glioma===
*BAF-47 -ve ([[AKA]] ''ANI1'') - virtually diagnostic.
{{Main|Pediatric-type diffuse low-grade glioma}}
**Endothelial cells +ve control.
*S-100 +ve.
**Few other brain tumours express it.
*Vimentin +ve (perinuclear condensation).


Others:
*GFAP +ve (focal - in tumour cells).
*EMA +ve (patchy cytoplasmic).
*Smooth muscle actin +ve.


==Oligodendroglioma==
===Circumscribed astrocytic gliomas===
===General===
* [[Pilocytic astrocytoma]] (PA)
*Arise from oligodendrocytes.
** [[Pilomyxoid astrocytoma]] (PMA)
* [[Pleomorphic xanthoastrocytoma]] (PXA)
* [[Subependymal giant cell astrocytoma]] (SEGA)
* [[Neuropathology_tumours#Astroblastoma|Astroblastoma MN1-altered]].
* [[Neuropathology_tumours#Chordoid glioma of the third ventricl|Chordoid glioma]].


Usual location:
====Astroblastoma====
*Fourth ventricle.
*No WHO grade yet.<ref>{{Ref WHOCNS|88}}</ref>
*Intramedullary spinal cord.
*Very rare superficial tumor of young age.<ref>{{Cite journal  | last1 = Narayan | first1 = S. | last2 = Kapoor | first2 = A. | last3 = Singhal | first3 = MK. | last4 = Jakhar | first4 = SL. | last5 = Bagri | first5 = PK. | last6 = Rajput | first6 = PS. | last7 = Kumar | first7 = HS. | title = Astroblastoma of cerebrum: A rare case report and review of literature. | journal = J Cancer Res Ther | volume = 11 | issue = 3 | pages = 667 | month =  | year =  | doi = 10.4103/0973-1482.140800 | PMID = 26458709 }}</ref>
*Large, cystic. Pushing margin towards CNS.
*Vasocentric growth, plump cells with absence of fibrillary pattern.
*GFAP+ve, Synaptohysin-ve, Olig-2-ve, focally EMA/panCK+ve. MIB-1: 1-18 %.
*Molecular profile overlaps with classical [[CNS-PNET]].
**Gene fusions invoving meningioma gene (MN1)<ref>{{Cite journal  | last1 = Sturm | first1 = D. | last2 = Orr | first2 = BA. | last3 = Toprak | first3 = UH. | last4 = Hovestadt | first4 = V. | last5 = Jones | first5 = DT. | last6 = Capper | first6 = D. | last7 = Sill | first7 = M. | last8 = Buchhalter | first8 = I. | last9 = Northcott | first9 = PA. | title = New Brain Tumor Entities Emerge from Molecular Classification of CNS-PNETs. | journal = Cell | volume = 164 | issue = 5 | pages = 1060-72 | month = Feb | year = 2016 | doi = 10.1016/j.cell.2016.01.015 | PMID = 26919435 }}</ref>


Prognosis by flavours (average survival):<ref name=Ref_PSNP98>{{Ref PSNP|98}}</ref>
*WHO grade II: 10-15 years.
*WHO grade III: 3-5 years.


===Microscopic===
<gallery>
Features:
File:Astroblastoma_HE_Specimen.jpg | HE. (WC/jensflorian)
*Highly cellular lesion composed of:
File:Astroblastoma_HE_papillae.jpg | HE. (WC/jensflorian)
**Cells resembling ''fried eggs'' (oligodendrocytes) with:
File:Astroblastoma.jpg | Astroblastoma (AFIP)
***Round nucleus - '''key feature'''.
</gallery>
***Distinct cell borders.
***Moderate-to-marked nuclear atypia.
***Clear cytoplasm - useful feature (if present).
****Some oligodendrogliomas have eosinophilic cytoplasm with focal perinuclear clearing.
**Acutely branched capillary sized vessels - "chicken-wire" like appearance.
***Abundant, delicate appearing; may vaguely resemble a paraganglioma at low power.
*Calcifications - important feature.<ref>URL: [http://www.emedicine.com/radio/topic481.htm http://www.emedicine.com/radio/topic481.htm].</ref>


Images:
====Chordoid glioma of the third ventricle====
*[http://commons.wikimedia.org/wiki/File:Oligodendroglioma1_high_mag.jpg Oligodendroglioma high mag. (WC)].
* WHO grade II.
*[http://commons.wikimedia.org/wiki/File:Oligodendroglioma1_low_mag.jpg Oligodendroglioma low mag. (WC)].
* Slowly growing, non-invasive, in adults.
* Clusters of epithelioid cells in mucinous stroma.
* Lymphocytic infiltrates, adjacent Rosenthal fibers.
* Fibrosis may be present.
* Few mitoses.
* [[GFAP]]+ve,  MIB-1 1-3%.
* [[TTF-1]]+ve.
* CD34+ve.
* [[IDH-1]]-ve, [[p53]]-ve.
* PRKCA D463H mutations.<ref>{{Cite journal  | last1 = Goode | first1 = B. | last2 = Mondal | first2 = G. | last3 = Hyun | first3 = M. | last4 = Ruiz | first4 = DG. | last5 = Lin | first5 = YH. | last6 = Van Ziffle | first6 = J. | last7 = Joseph | first7 = NM. | last8 = Onodera | first8 = C. | last9 = Talevich | first9 = E. | title = A recurrent kinase domain mutation in PRKCA defines chordoid glioma of the third ventricle. | journal = Nat Commun | volume = 9 | issue = 1 | pages = 810 | month = 02 | year = 2018 | doi = 10.1038/s41467-018-02826-8 | PMID = 29476136 }}</ref>


Notes:
<gallery>
*Few neural tumours have round nuclei - DDx:
File:NP op 20201028 009.jpg | Chordoid Glioma. (WC/jensflorian)
**Oligodendroglioma.
</gallery>
**Lymphoma.
**Clear cell variant of ependymoma.
**Germ cell tumour (dysgerminoma/seminoma).


====Histologic grading====
Come in two flavours:
# WHO grade II.
#*This is most oligodendrogliomas.
# WHO grade III.
#*Features for calling high grade:<ref name=Ref_PSNP98>{{Ref PSNP|98}}</ref>
#**Endothelial hypertrophy.
#***Plump/large endothelial cells.
#**Necrosis.
#**High mitotic rate (6 mitoses/10 HPF for whatever "HPF" means, see [[HPFitis]]).


===IHC===
===Ependymal tumours===
Features:
* [[Subependymoma]]
*GFAP +ve.
* [[Myxopapillary Ependymoma]]
*EMA +ve.
* [[Ependymoma]]
* Anaplastic ependymoma


===Molecular pathology===
==Choroid plexus tumours==
Losses of 1p and 19q both helps with diagnosis and is prognostic:<ref name=pmid18565359>{{cite journal |author=Fontaine D, Vandenbos F, Lebrun C, Paquis V, Frenay M |title=[Diagnostic and prognostic values of 1p and 19q deletions in adult gliomas: critical review of the literature and implications in daily clinical practice] |language=French |journal=Rev. Neurol. (Paris) |volume=164 |issue=6-7 |pages=595–604 |year=2008 |pmid=18565359 |doi=10.1016/j.neurol.2008.04.002 |url=}}</ref>
* [[Choroid plexus papilloma]]
*Greater chemosensitivity
* Atypical choroid plexus papilloma
*Better prognosis.
* [[Choroid plexus carcinoma]]


==Meningioma==
==Other neuroepithelial tumours==
{{Main|Meningioma}}
* [[Neuropathology_tumours#Cribiform_neuroepithelial_tumour|Cribifiorm neuroepithelial tumour]].
===General===
*Very common.
*May be part of a syndrome.


===Microscopic===
Features (memory device ''WTC''):
*Whorled appearance - '''key feature'''.
*Thick-walled blood vessels, usually prominent.
*Calcification.


Grading: see ''[[meningioma]]''.
===Cribiform neuroepithelial tumour===
AKA: '''CRINET'''.
*Not listed in the current WHO classification.
*First description in 2009.<ref>{{Cite journal  | last1 = Hasselblatt | first1 = M. | last2 = Oyen | first2 = F. | last3 = Gesk | first3 = S. | last4 = Kordes | first4 = U. | last5 = Wrede | first5 = B. | last6 = Bergmann | first6 = M. | last7 = Schmid | first7 = H. | last8 = Frühwald | first8 = MC. | last9 = Schneppenheim | first9 = R. | title = Cribriform neuroepithelial tumor (CRINET): a nonrhabdoid ventricular tumor with INI1 loss and relatively favorable prognosis. | journal = J Neuropathol Exp Neurol | volume = 68 | issue = 12 | pages = 1249-55 | month = Dec | year = 2009 | doi = 10.1097/NEN.0b013e3181c06a51 | PMID = 19915490 }}</ref>
*Around ventricles.<ref>{{Cite journal  | last1 = Arnold | first1 = MA. | last2 = Stallings-Archer | first2 = K. | last3 = Marlin | first3 = E. | last4 = Grondin | first4 = R. | last5 = Olshefski | first5 = R. | last6 = Biegel | first6 = JA. | last7 = Pierson | first7 = CR. | title = Cribriform neuroepithelial tumor arising in the lateral ventricle. | journal = Pediatr Dev Pathol | volume = 16 | issue = 4 | pages = 301-7 | month =  | year =  | doi = 10.2350/12-12-1287-CR.1 | PMID = 23495723 }}</ref>
*Young children.<ref>{{Cite journal  | last1 = Park | first1 = JY. | last2 = Kim | first2 = E. | last3 = Kim | first3 = DW. | last4 = Chang | first4 = HW. | last5 = Kim | first5 = SP. | title = Cribriform neuroepithelial tumor in the third ventricle: a case report and literature review. | journal = Neuropathology | volume = 32 | issue = 5 | pages = 570-6 | month = Oct | year = 2012 | doi = 10.1111/j.1440-1789.2011.01293.x | PMID = 22239490 }}</ref>
*Small undifferentiated cells arranged in cribriform strands and trabeculae of varying thickness.
*MAP2+ve, Synaptophysin+ve, CK+/-ve. MIB-1: 30%.
*INI-1 loss, but no rhabdoid features and good prognosis.
*Stable genomic profile.<ref>{{Cite journal  | last1 = Gessi | first1 = M. | last2 = Japp | first2 = AS. | last3 = Dreschmann | first3 = V. | last4 = Zur Mühlen | first4 = A. | last5 = Goschzik | first5 = T. | last6 = Dörner | first6 = E. | last7 = Pietsch | first7 = T. | title = High-Resolution Genomic Analysis of Cribriform Neuroepithelial Tumors of the Central Nervous System. | journal = J Neuropathol Exp Neurol | volume = 74 | issue = 10 | pages = 970-4 | month = Oct | year = 2015 | doi = 10.1097/NEN.0000000000000239 | PMID = 26352987 }}</ref>


==Peripheral nerve sheath tumours==
==Neuronal and mixed neuronal/glial tumours==
{{Main|Peripheral nerve sheath tumours}}
* [[Desmoplastic infantile astrocytoma]] / ganglioglioma (DIA/DIG)
A classification:<ref name=pmid17893219>{{cite journal |author=Wippold FJ, Lubner M, Perrin RJ, Lämmle M, Perry A |title=Neuropathology for the neuroradiologist: Antoni A and Antoni B tissue patterns |journal=AJNR Am J Neuroradiol |volume=28 |issue=9 |pages=1633–8 |year=2007 |month=October |pmid=17893219 |doi=10.3174/ajnr.A0682 |url=http://www.ajnr.org/cgi/reprint/28/9/1633}}</ref>
* [[Dysembryoplastic neuroepithelial tumour]]
*Benign:
* [[Central Neurocytoma]] / Extraventricular [[neurocytoma]]
**Schwannoma.
* Cerebellar liponeurocytoma
**Neurofibroma.
* [[Papillary glioneuronal tumour]] (PGNT)
**Perineurioma.
* [[Rosette-forming glioneuronal tumour of the fourth ventricle]] (RGNT)
**Traumatic neuroma.
* Gangliocytoma / Ganglioglioma
*Malignant:
* Dysplastic ganglioglioma of the cerebellum ([[Lhermitte-Duclos disease]])
**Malignant peripheral nerve sheath tumour (MPNST).
* [[Paraganglioma]]


==Schwannoma==
===Desmoplastic infantile astrocytoma / Desmoplastic infantile ganglioglioma===
* Abbreviated ''DIA'' or ''DIG''.
* ICD-O code: 9412/1
* Large, superficial, cystic tumor of the infancy.
* Biologic course corresponds to WHO grade I.
* Very rare, included in the WHO since 1993.
* Prominent desmoplastic stroma.
* Astrocytic cells within stroma.
**GFAP+.
**MIB-1 usu. 1%.
* Frequent BRAF V600E or V600D mutations.<ref>{{Cite journal  | last1 = Wang | first1 = AC. | last2 = Jones | first2 = DTW. | last3 = Abecassis | first3 = IJ. | last4 = Cole | first4 = BL. | last5 = Leary | first5 = SES. | last6 = Lockwood | first6 = CM. | last7 = Chavez | first7 = L. | last8 = Capper | first8 = D. | last9 = Korshunov | first9 = A. | title = Desmoplastic Infantile Ganglioglioma/Astrocytoma (DIG/DIA) are Distinct Entities with Frequent BRAFV600 Mutations. | journal = Mol Cancer Res | volume =  | issue =  | pages =  | month = Jul | year = 2018 | doi = 10.1158/1541-7786.MCR-17-0507 | PMID = 30006355 }}</ref>
*Single case with BRAF indel or BRAF fusion.
<gallery>
File:DIG-histology.jpg | Histopathology of DIG (HE stain)
File:DIG-histology2.jpg | Prominent ganglioid cells in DIG (HE stain)
</gallery>


{{Main|Peripheral nerve sheath tumours#Schwannoma}}
===Cerebellar liponeurocytoma===
===General===
* Previously called ''lipomatous medulloblastoma'' (name changed in WHO 2000).
*Tumour of tissue surrounding a nerve.
* Mean age: 50 years.
**Axons adjacent to the tumour are normal... but may be compressed.
* As the name states: A tumour of the cerebellum.
** But cases outside cerebellum reported that would qualify.<ref>{{Cite journal  | last1 = Gupta | first1 = K. | last2 = Salunke | first2 = P. | last3 = Kalra | first3 = I. | last4 = Vasishta | first4 = RK. | title = Central liponeurocytoma: case report and review of literature. | journal = Clin Neuropathol | volume = 30 | issue = 2 | pages = 80-5 | month =  | year =  | doi =  | PMID = 21329617 }}</ref>
* WHO grade II <ref>{{Cite journal  | last1 = Nishimoto | first1 = T. | last2 = Kaya | first2 = B. | title = Cerebellar liponeurocytoma. | journal = Arch Pathol Lab Med | volume = 136 | issue = 8 | pages = 965-9 | month = Aug | year = 2012 | doi = 10.5858/arpa.2011-0337-RS | PMID = 22849747 }}</ref> (upgraded from WHO grade I in 2007)<ref>{{Cite journal  | last1 = Brat | first1 = DJ. | last2 = Parisi | first2 = JE. | last3 = Kleinschmidt-DeMasters | first3 = BK. | last4 = Yachnis | first4 = AT. | last5 = Montine | first5 = TJ. | last6 = Boyer | first6 = PJ. | last7 = Powell | first7 = SZ. | last8 = Prayson | first8 = RA. | last9 = McLendon | first9 = RE. | title = Surgical neuropathology update: a review of changes introduced by the WHO classification of tumours of the central nervous system, 4th edition. | journal = Arch Pathol Lab Med | volume = 132 | issue = 6 | pages = 993-1007 | month = Jun | year = 2008 | doi = 10.1043/1543-2165(2008)132[993:SNUARO]2.0.CO;2 | PMID = 18517285 }}</ref>
*ICD-O code: 9506/1


===Microscopic===
====Histo====
Features:<ref name=pmid17893219/>
* Advanced neuronal and lipomatous differentiation.
*Antoni tissue (type A and type B).
* Neurocytes: round to oval nuclei with clear cytoplasm.
*Verocay bodies - paucinuclear area surrounded by nuclei.
* Quite cellular.
* Mitoses almost absent.  


Notes:
====IHC====
*Tumour does ''not'' smear well.<ref>MUN. 24 November 2010.</ref>
* [[GFAP]] +/-ve (focal).
* [[MAP2]] +ve.
* Synaptophysin +ve.
* NeuN +ve.
* MIB-1: usu 1-3%.


====Antoni A====
====Molecular====
*Cellular.
* Distinct methylation profile.
*'Fibrillary, polar, elongated'.
* Recurent losses on 2p and Chr. 14.<ref>{{Cite journal  | last1 = Capper | first1 = D. | last2 = Stichel | first2 = D. | last3 = Sahm | first3 = F. | last4 = Jones | first4 = DTW. | last5 = Schrimpf | first5 = D. | last6 = Sill | first6 = M. | last7 = Schmid | first7 = S. | last8 = Hovestadt | first8 = V. | last9 = Reuss | first9 = DE. | title = Practical implementation of DNA methylation and copy-number-based CNS tumor diagnostics: the Heidelberg experience. | journal = Acta Neuropathol | volume =  | issue =  | pages =  | month = Jul | year = 2018 | doi = 10.1007/s00401-018-1879-y | PMID = 29967940 }}</ref>


Comment: May look somewhat like scattered matchsticks.
<gallery>
====Antoni B====
File:Cerebellar liponeurocytoma.jpg | Liponeurocytoma, HE (WC/Marvin101).
*Loose microcystic tissue.
File:Liponeurocytoma Synaptophysin.jpg | Liponeurocytoma, Synapto (WC/Marvin101).
*Adjacent to Antoni A.
File:Cerebellar Liponeurocytoma HE.jpg | Liponeurocytoma, HE (WC/jensflorian).
File:Cerebellar Liponeurocytoma Synaptophysin.jpg | Liponeurocytoma, Synapto (WC/jensflorian).
</gallery>


Micrographs:
====DDx====
*[http://www.pathguy.com/~lulo/lulo0003.htm Antoni A (pathguy.com)].
* [[Medulloblastoma]]
*[http://www.ajnr.org/cgi/content/full/28/9/1633/F8 Antoni A & Antoni B side-by-side (ajnr.org)].
* [[Neurocytoma]]


==Neurofibroma==
===Gangliocytoma===
{{Main|Peripheral nerve sheath tumours#Neurofibroma}}
* Grade I WHO neuronal tumour.
===General===
** ICD-O code: 9492/0
*May be a part of [[neurofibromatosis]] 1.
* Groups of irregular large neurons.
*Composed of Schwann cells, axons, fibrous material.<ref name=pmid17893219/>
* Non-neoplastic, reticulin-rich glial stroma.


===Microscopic===
===Ganglioglioma===
Features:<ref name=pmid17893219/>
:'''Not''' to be confused with ''[[ganglioneuroma]]''.
*Plexiform growth pattern - "bag of worms".
====General====
*Gangliolioma: Grade I WHO mixed neuronal-glial tumour (ICD-O code: 9505/1).
*Anaplastic ganglioglioma: Grade III (ICD-O: 9505/3)
*Rare (approx. 0.5% of all CNS tumors).
*Usu. temporal lobe.
*Predominantly children (mean age: 9 years).
*Recognized as a cause of [[epilepsy]].<ref name=pmid12125968>{{Cite journal  | last1 = Im | first1 = SH. | last2 = Chung | first2 = CK. | last3 = Cho | first3 = BK. | last4 = Lee | first4 = SK. | title = Supratentorial ganglioglioma and epilepsy: postoperative seizure outcome. | journal = J Neurooncol | volume = 57 | issue = 1 | pages = 59-66 | month = Mar | year = 2002 | doi =  | PMID = 12125968 }}</ref>
*Favourable prognosis (survival rates up to 97%)
**Insufficient data für anaplastic ganglioglioma.


Image:
====Macroscopic====
*[http://commons.wikimedia.org/wiki/File:Neurofibroma_(1).jpg Neurofibroma - low mag. (WC)].
*Circumscribed lesion.
*[http://commons.wikimedia.org/wiki/File:Neurofibroma_(2).jpg Neurofibroma - high mag. (WC)].
*Usu. contrast enhancing.
*[http://commons.wikimedia.org/wiki/File:Neurofibroma_(3).jpg Neurofibroma - high mag. (WC)].
*Solid, but intracortical cysts may be present.
*Little mass effect.


==Ganglioneuroma==
===General===
*[[AKA]] ganglioma.<ref>URL: [http://medical-dictionary.thefreedictionary.com/ganglioma http://medical-dictionary.thefreedictionary.com/ganglioma]. Accessed on: 8 November 2010.</ref>
*May be retroperitoneal.


===Microscopic===
====Microscopic====
Features:
Features:
*Ganglion cells - '''key feature'''.
*Dysplastic neurons.
**Large cells with large nucleus.
**Out of regular architecture / abnormal location.
***Prominent nucleolus.
**Cytomegaly
*Disordered fibrinous-like material.
**Clustering
*Eosinophilic granular bodies.<ref>R. Kiehl. 8 November 2010.</ref>
**Binucleated (very occassionally).
*Atypical glia.
*Eosinophilic granular bodies.
*Calcification.
*Prominent capillary network.
*Lymphocytic cuffing.
*May contain some reticulin.
*Glial component may resemble:
**Fibrillary astrocytoma.
**Oligodendroglioma.
**Pilocytic astrocytoma.


Images:
Anaplastic ganglioglioma:
*[http://it.wikipedia.org/wiki/File:Ganglioneuroma_(1).jpg Ganglioneuroma (WC)].
*Brisk mitotic activity
*[http://www.webpathology.com/image.asp?n=4&Case=84 Ganglioneuroma (webpathology.com)].
*Necrosis


See: ''[[Adrenal gland]]''.
====IHC====
*Neurons:
**[[MAP2]] +ve
**Synaptophysin +ve
** Neurofilament +ve
*Glia:
**CD34+/-ve
*BRAF V600E +ve (approx. 25%, mainly ganglion cells).


==Ependymoma==
====Molecular====
===General===
*BRAF V600E-mutated(approx. 25%).
*Called the forgotten glial tumour.
*IDH1/2 wt.
*No 1p/19q codeletion.
*Usu. Chr. 7 gain.
*CDKN2A deletions in anaplastic ganglioglioma.  


Comes in two flavours:
====DDx:====
#Ependymoma (not otherwise specified).
*[[DNT]].
#Myxopapillary ependymoma.
*[[Oligodendroglioma]].
#*Classically at filum terminale.
*Trapped cortical neurons in diffuse astrocytoma.
*Papillary glioneuronal tumor.
*Dysembryoplastic neuroepithelial tumor.


===Microscopy===
====Images====
====Classic ependymoma====
<gallery>
Features:
File:Ganglioglioma lymphocytic cuffing PAS.jpg | Lymphocytic cuffing in ganglioglioma (WC/jensflorian)
*Cells have a "tadpole-like" morphology.
File:Ganglioglioma calcification.jpg | Calcification in ganglioglioma (WC/jensflorian)
**May also be described as ''ice cream cone-shaped''.<ref>[http://www.pathology.vcu.edu/WirSelfInst/tumor-2.html http://www.pathology.vcu.edu/WirSelfInst/tumor-2.html]</ref>
File:Ganglioglioma Cd34 x200.jpg | CD34 immunostain in ganglioglioma (WC/jensflorian)
*Rosettes - cells arranged in a pseudoglandular fashion.
File:Anaplastic ganglioglioma HE.jpg | Pleomorphic ganglion cells in ganglioglioma (WC/jensflorian)
*"Nucleus free zones" - cells arranged around a blood vessel (perivascular pseudorosettes); nuclei of cells distant from the blood vessel, i.e. a rim of cytoplasm (from tumour cells) surrounds the blood vessel.
</gallery>
''Perivascular pseudorosettes'' = (tumour) cells arranged around a blood vessel; nuclei of cells distant from the blood vessel, i.e. rim of cytoplasm (from tumour cells) surround blood vessel (nucleus-free zone)
*[http://path.upmc.edu/cases/case142.html Ganglioglioma - case 1 (upmc.edu)].
*[http://path.upmc.edu/cases/case282.html Ganglioglioma - case 2 (upmc.edu)].


**The nucleus free zone is composed of tumour cell cytoplasm that is adjacent to an unseen blood vessel.
===Lhermitte-Duclos disease===
*Nuclear feature monotonous, i.e. "boring".<ref>MUN. 6 Oct 2009.</ref>
*Abbreviated ''LDD''.
**There is little variation in size, shape and staining.
*[[AKA]] ''dysplastic cerebellar gangliocytoma''.<ref name=pmid20060133>{{Cite journal  | last1 = Yağci-Küpeli | first1 = B. | last2 = Oguz | first2 = KK. | last3 = Bilen | first3 = MA. | last4 = Yalçin | first4 = B. | last5 = Akalan | first5 = N. | last6 = Büyükpamukçu | first6 = M. | title = An unusual cause of posterior fossa mass: Lhermitte-Duclos disease. | journal = J Neurol Sci | volume = 290 | issue = 1-2 | pages = 138-41 | month = Mar | year = 2010 | doi = 10.1016/j.jns.2009.12.010 | PMID = 20060133 }}</ref>
*[[AKA]] ''dysplastic gangliocytoma of the cerebellum''.
{{Main|Lhermitte-Duclos disease}}
<gallery>
File:Dysplastic_gangliocytoma_lhermitte_duclos.jpg | Dysplastic gangliocytoma (low mag).
</gallery>


Images:
===Papillary glioneuronal tumour===
*[http://commons.wikimedia.org/wiki/File:Ependymoma_intermed_mag.jpg Ependymoma - intermed. mag. (WC)].
* Abbreviated ''PGNT''.
*[http://commons.wikimedia.org/wiki/File:Ependymoma_low_intermed_mag.jpg Ependymoma - low mag. (WC)].
* A benign, supratentorial tumor of childhood.
** Biologic course corresponds to WHO grade I.
** Before WHO 2000, considered a [[Ganglioglioma]] variant.
*Prominent pseudopapillary architecture.
*Neurocytes to medium-sized ganglion cells.
*GFAP+ core, GFAP- layer
*Rosenthal fibers, Eosinophilic Granular bodies and lymphocytic cuffing may be present.
<gallery>
File:PGNT_HE_stain.jpg | PGNT (HE) (WC/jensflorian)
</gallery>


DDx (classic ependymoma):
===Rosette-forming glioneuronal tumour of the fourth ventricle===
*Subependymoma.
* Abbreviated ''RGNT''.
*Glioblastoma (GBM).
* Provisional ICD-O code: 9509/1
**Invasive border = GBM; circumscribed border of lesion = ependymoma.
* A rare benign infratentorial tumour of the midline of children and adults.
* Biologic course corresponds to WHO grade I.
* Glial component corresponds to [[pilocytic astrocytoma]].
* Neurocytic rosettes.
* Eosinopil fibrillary cores / pseudorosettes.
* GFAP+ in fibrillary areas, Syn+ in rosettes.
* Neurocytic cells: MAP2+
* MIB-1 usu. below 3%.
<gallery>
File:Histology RGNT HE.jpg | RGNT, HE stain (WC/jensflorian).
File:RGNT HE 2.jpg | RGNT, higher magnification (WC/jensflorian).
</gallery>


====Myxopapillary ependymoma====
===Polymorphous low-grade tumor of the young (PLNTY)===
Features:
* [[Pediatric-type diffuse low-grade glioma#Diffuse low-grade glioma, MAPK pathway-altered|Polymorphous low-grade tumor of the young (PLNTY)]]
*Perivascular pseudorosettes:
**Myxoid material surround blood vessels.
***Myxoid material surrounded by tumour cells.


Images:
==Pineal tumours==
*[http://careers.bmj.com/article-images/cf0708.f2_default.gif Myxopapillary ependymoma (bmj.com)] - part of [http://careers.bmj.com/careers/advice/view-article.html?id=351 careers.bmj.com article on paediatric pathology].
{{Main|Pineal gland}}
*[http://commons.wikimedia.org/wiki/File:Myxopapillary_ependymoma.jpg Myxopapillary ependymoma - cytology (WC)].


====Grading====
* [[Pineocytoma]]
Easy:
* [[Pineal parenchymal tumour of intermediate differentiation]]
*Subependymoma = WHO grade I.
* [[Pineoblastoma]]
*Myxopapillary ependymoma = WHO grade I.
* [[Papillary tumour of the pineal region]]
Not-so-easy:
*Classic ependymoma = WHO grade II.
*Anaplastic ependymoma = WHO grade III.


Grade II vs. Grade III:
==Embryonal tumours==
*Cellular density.
* [[Atypical teratoid/rhabdoid tumour]] (AT/RT) or (AT-RT)
*Mitoses.
* [[Medulloblastoma]]
*Necrosis.
* [[Primitive neuroectodermal tumour]] (PNET)
*Microvascular proliferation.
* [[Embryonal tumour with abundant neuropil and true rosettes]] (ETANTR)


Notes:
DDx:
*Many tumours fall between grade II and grade III.  These are called "indeterminate" by many.
* [[Ewing sarcoma]]
* [[Sarcoma with CIC-rearrangement]]


===IHC===
==Peripheral nerve sheath tumours==
*Reticulin.
{{Main|Peripheral nerve sheath tumours}}
*GFAP.
A classification:<ref name=pmid17893219>{{cite journal |author=Wippold FJ, Lubner M, Perrin RJ, Lämmle M, Perry A |title=Neuropathology for the neuroradiologist: Antoni A and Antoni B tissue patterns |journal=AJNR Am J Neuroradiol |volume=28 |issue=9 |pages=1633–8 |year=2007 |month=October |pmid=17893219 |doi=10.3174/ajnr.A0682 |url=http://www.ajnr.org/cgi/reprint/28/9/1633}}</ref>
*MIB-1.
'''Benign:'''
*[[Schwannoma]].
*[[Neurofibroma]].
*[[Perineurioma]].
*Ganglioneuroma.
**[[Traumatic neuroma]].
'''Malignant:'''
*[[Malignant peripheral nerve sheath tumour]] (MPNST).


==Choroid plexus papilloma==
===Ganglioneuroma===
===Microscopy===
:'''Not''' to be confused with ''[[ganglioglioma]]''.
Features:
*[[AKA]] ganglioma.<ref>URL: [http://medical-dictionary.thefreedictionary.com/ganglioma http://medical-dictionary.thefreedictionary.com/ganglioma]. Accessed on: 8 November 2010.</ref>
*Papillae.
{{Main|Ganglioneuroma}}
*Psammoma bodies.


Image:
*[http://commons.wikimedia.org/wiki/File:Choroid_plexus_papilloma_micrograph.jpg Choroid plexus papilloma (WC)].


==Chordoma==
===General===
*Location: usually sacrum or clivus.


===Microscopic===
==Meningioma==
Features:<ref name=Ref_DCHH184>{{Ref DCHH|184}}</ref>
{{Main|Meningioma}}
*Architecture: islands of cells surrounded by fibrous tissue.
**Also described as "lobulated" architecture; may not be apparent.
*Myxoid background - grey extracellular material, variable amount present.
*Mixed cell population:
*#Abundant eosinophilic cytoplasm.
*#''Physaliphorous cells'' or ''bubble cells'' - '''key feature'''.
*#*Have a very large clear bubble with a sharp border; bubble does not compress nucleus - nucleus may be in bubble.


Image(s):
==Chordoma==
*[http://www.surgical-pathology.com/Chordoma4_image.htm Chordoma - crappy quality image (surgical-pathology.com)].
{{Main|Chordoma}}
 
===IHC===
Features:
*S100 +ve.
*CK +ve.
*Brachyury +ve.
**Protein important for axial development, affects notochord development.<ref>URL:[http://www.ncbi.nlm.nih.gov/omim/601397 http://www.ncbi.nlm.nih.gov/omim/601397]. Accessed on: 18 May 2010.</ref>
**''Brachyury'' literally means ''short tail''.<ref>URL: [http://www.jstor.org/pss/86845 http://www.jstor.org/pss/86845]. Accessed on: 18 May 2010.</ref>


==Hemangioblastoma==
==Hemangioblastoma==
===General===
{{Main|Hemangioblastoma}}
*Usually ''cerebellar''.
*Associated with [[von Hippel-Lindau syndrome]].
 
===Microscopic===
Features:<ref>URL: [http://emedicine.medscape.com/article/340994-media http://emedicine.medscape.com/article/340994-media]. Accessed on: 23 June 2010.</ref>
*Vascular.
*Polygonal stromal cells with:
**Hyperchromatic nuclei.
**Vacuolar cytoplasm.


Images:
==CNS lymphoma==
*[http://commons.wikimedia.org/wiki/File:Cerebellar_hemangioblastoma_intermed_mag.jpg Hemangioblastoma - intermed. mag. (WC)].
Classification:
*[http://commons.wikimedia.org/wiki/File:Cerebellar_hemangioblastoma_high_mag.jpg Hemangioblastoma - high mag. (WC)].
*Primary CNS lymphoma.
*Non-primary CNS lymphoma - see ''[[lymphoma]]'' article.
==Medulloblastoma==
===General===
*Mostly paediatric population.  
*May be seen as a component of [[nevoid basal cell carcinoma syndrome]] (NBCCS).


===Gross===
===General - primary CNS===
*Location: cerebellum - '''key feature'''.
*Classically periventicular distribution.
**Morphologically identical supratentorial tumours are called ''primitive neuroepithelial tumour'' (PNET).
*Usually large B cell; can be considered a type of [[diffuse large B cell lymphoma]] (DLBCL).
**Prognosis of CNS (DLBCL) lymphomas worse than nodal (non-CNS) DLBCL.<ref name=pmid19925562>{{cite journal |author=Raoux D, Duband S, Forest F, ''et al.'' |title=Primary central nervous system lymphoma: Immunohistochemical profile and prognostic significance |journal=Neuropathology |volume=30 |issue=3 |pages=232–40 |year=2010 |month=June |pmid=19925562 |doi=10.1111/j.1440-1789.2009.01074.x |url=}}</ref>


===Microscopic===
===Microscopic===
Features:<ref>URL: [http://moon.ouhsc.edu/kfung/jty1/neurotest/Q93-Ans.htm http://moon.ouhsc.edu/kfung/jty1/neurotest/Q93-Ans.htm]. Accessed on: 26 October 2010.</ref>
Features:
*Homer-Wright rosettes= rosette with a meshwork of fibers (neuropil) at the centre.<ref>{{cite journal |author=Wippold FJ, Perry A |title=Neuropathology for the neuroradiologist: rosettes and pseudorosettes |journal=AJNR Am J Neuroradiol |volume=27 |issue=3 |pages=488–92 |year=2006 |month=March |pmid=16551982 |doi= |url=}}</ref>
*Large cell lymphoma.
**Size = 2x diameter normal lymphocyte.
**Nucleolus - common.
*Perivascular clustering.
 
====Images====
www:
*[http://frontalcortex.com/?page=image&topic=1&qid=1237 CNS lymphoma (frontalcortex.com)].
*[http://path.upmc.edu/cases/case403.html Primary CNS lymphoma - several images (upmc.edu)].
<gallery>
Image:Primary CNS lymphoma - low mag.jpg | CNS lymphoma - low mag. (WC)
Image:Primary CNS lymphoma - intermed mag.jpg | CNS lymphoma - intermed. mag. (WC)
Image:Primary CNS lymphoma - high mag.jpg | CNS lymphoma - high mag. (WC)
Image:Primary CNS lymphoma - very high mag.jpg | CNS lymphoma - very high mag. (WC)
</gallery>
<gallery>
Image: CNS lymphoma (1) B-cell type.jpg | CNS lymphoma. (WC/KGH)
Image: CNS lymphoma (2) B-cell type.jpg | CNS lymphoma. (WC/KGH)
</gallery>


Image:
===IHC===
*[http://moon.ouhsc.edu/kfung/jty1/neurotest/Q93-Ans.htm Medulloblastoma (ouhsc.edu)].
Can be subclassified in ''GCB (germinal centre B-cell-like)'' and ''non-GCB'' by CD10, Bcl-6, MUM1/IRF-4, and Bcl-2.<ref name=pmid19925562/>


====Subtypes====
Common pattern:
*Classic medulloblastoma (~85% of all medulloblastomas).
*[[CD20]] +ve - key stain.
*Variants of medulloblastoma (~15% of all medulloblastomas together):
*CD3 -ve.
*#Anaplastic variant.
*Ki-67 ~40%.
*#Large cell variant.
*Bcl-6 +ve.
*#Desmoplastic/nodular medulloblastoma (DNMB).
*Bcl-1 -ve.
*#Medulloblastoma with extensive nodularity (MBEN).


Notes:
*Prognosis:<ref name=pmid18841049>{{cite journal |author=Gulino A, Arcella A, Giangaspero F |title=Pathological and molecular heterogeneity of medulloblastoma |journal=Curr Opin Oncol |volume=20 |issue=6 |pages=668–75 |year=2008 |month=November |pmid=18841049 |doi=10.1097/CCO.0b013e32831369f4 |url=}}</ref><ref name=pmid20940197>{{cite journal |author=Rutkowski S, von Hoff K, Emser A, ''et al.'' |title=Survival and Prognostic Factors of Early Childhood Medulloblastoma: An International Meta-Analysis |journal=J Clin Oncol |volume=28 |issue=33 |pages=4961–4968 |year=2010 |month=November |pmid=20940197 |doi=10.1200/JCO.2010.30.2299 |url=}}</ref> DNMB & MBEN > classic > anaplastic variant, large cell variant.


=====Anaplastic variant=====
Features:
*Larger cells.
*Severe anaplasia.
*Polygonal cells.


==Primitive neuroepithelial tumour==  
==Ganglioneuroblastoma==
{{Main|Neuroblastoma}}
===General===
===General===
*Abbreviated ''PNET''.
*Uncommon.
*Part of the ''neuroblastic tumours'' group which includes:<ref name=pmid10421272>{{cite journal |author=Shimada H, Ambros IM, Dehner LP, Hata J, Joshi VV, Roald B |title=Terminology and morphologic criteria of neuroblastic tumors: recommendations by the International Neuroblastoma Pathology Committee |journal=Cancer |volume=86 |issue=2 |pages=349–63 |year=1999 |month=July |pmid=10421272 |doi= |url=}}</ref>
**[[Ganglioneuroma]] (benign).
**Ganglioneuroblastoma (intermediate).
**[[Neuroblastoma]] (aggressive).


===Microscopic===
===Microscopic===
Features:
Features:
*See ''medulloblastoma''.
*Ganglion-like cells with a prominent nucleolus.
*Small undifferentiated cells with scant cytoplasm.
<gallery>
Image:Adrenal Ganglioneuroblastoma LP CTR.jpg|thumb|Adrenal Ganglioneuroblastoma  - Low power (SKB)
Image:Adrenal Ganglioneuroblastoma MP CTR.jpg|thumb|Adrenal Ganglioneuroblastoma  - Medium power (SKB)
Image:Adrenal Ganglioneuroblastoma HP CTR.jpg|thumb|Adrenal Ganglioneuroblastoma - High power (SKB)
Image:Adrenal Ganglioneuroblastoma HP3 CTR.jpg|thumb|Adrenal Ganglioneuroblastoma - High power (SKB)
Image:Adrenal Ganglioneuroblastoma HP2 CTR.jpg|thumb|Adrenal Ganglioneuroblastoma  - High power (SKB)
</gallery>
Images:
*[http://path.upmc.edu/cases/case530.html Ganglioneuroblastoma - several images (upmc.edu)].
 
===IHC===
*NSE +ve -- small cells.


DDx: Embryonal tumor with abundant neuropil and true rosettes (ETANTR).<ref>{{cite journal |author=Buccoliero AM, Castiglione F, Degl'Innocenti DR, ''et al.'' |title=Embryonal tumor with abundant neuropil and true rosettes: morphological, immunohistochemical, ultrastructural and molecular study of a case showing features of medulloepithelioma and areas of mesenchymal and epithelial differentiation |journal=Neuropathology |volume=30 |issue=1 |pages=84–91 |year=2010 |month=February |pmid=19563506 |doi=10.1111/j.1440-1789.2009.01040.x |url=}}</ref>
==Lesions of the sella turcica==
{{Main|Pituitary gland}}
Lesions of the sella turcica, the pituitary gland environs, is a topic for it self. The differential diagnosis for lesions in this area includes:
*[[Pituitary adenoma]].
*[[Craniopharyngioma]].
*[[Rathke cleft cyst]].  
*[[Germ cell tumour]].
*[[Meningioma]].
*[[Pilomyxoid astrocytoma]] - in children.


==See also==
==See also==
Jensflorian
Account-creators
1,040

edits

Retrieved from "https://librepathology.org/wiki/Special:MobileDiff/2991...52004"

Navigation menu