Esthesioneuroblastoma pathophysiology: Difference between revisions

Jump to navigation Jump to search
VisualWikitext
No edit summary
(Mahshid)
 
(37 intermediate revisions by 2 users not shown)
Line 3: Line 3:
{{CMG}}{{AE}}{{Simrat}}
{{CMG}}{{AE}}{{Simrat}}
==Overview==
==Overview==
Genetic mutations involved in the pathogenesis of esthesioneuroblastoma include chromosomal gains in ''7q11'' and ''20q'' and deletions in ''2q'', ''5q'', ''6p'', ''6q'', and ''18q''. On gross pathology, a soft, hemorrhagic, polypoid appearance, and rich, fragile vascular supply are characteristic findings of esthesioneuroblastoma. On microscopic histopathological analysis, arrangements of cells into rosettes or pseudorosettes are characteristic findings of esthesioneuroblastoma.<ref name="radio"> Esthesioneuroblastoma. Radiopedia(2015) http://radiopaedia.org/articles/olfactory-neuroblastoma Accessed on January 25, 2016</ref><ref name="librepathology">  Esthesioneuroblastoma. Libre pathology(2015) http://librepathology.org/wiki/index.php/Olfactory_neuroblastoma Accessed on January 25, 2015</ref><ref>Hyams, V. J. (1988). Tumors of the upper respiratory tract and ear. Washington, D.C.: Armed Forces Institute of Pathology.</ref><ref name="pmid8630875">{{cite journal| author=Hirose T, Scheithauer BW, Lopes MB, Gerber HA, Altermatt HJ, Harner SG et al.| title=Olfactory neuroblastoma. An immunohistochemical, ultrastructural, and flow cytometric study. | journal=Cancer | year= 1995 | volume= 76 | issue= 1 | pages= 4-19 | pmid=8630875 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=8630875  }} </ref><ref name="pmid18408657">{{cite journal| author=Guled M, Myllykangas S, Frierson HF, Mills SE, Knuutila S, Stelow EB| title=Array comparative genomic hybridization analysis of olfactory neuroblastoma. | journal=Mod Pathol | year= 2008 | volume= 21 | issue= 6 | pages= 770-8 | pmid=18408657 | doi=10.1038/modpathol.2008.57 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=18408657  }} </ref><ref name="pmid15272537">{{cite journal| author=Mhawech P, Berczy M, Assaly M, Herrmann F, Bouzourene H, Allal AS et al.| title=Human achaete-scute homologue (hASH1) mRNA level as a diagnostic marker to distinguish esthesioneuroblastoma from poorly differentiated tumors arising in the sinonasal tract. | journal=Am J Clin Pathol | year= 2004 | volume= 122 | issue= 1 | pages= 100-5 | pmid=15272537 | doi=10.1309/QD0K-9Q1J-BH6B-5GQQ | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15272537  }} </ref><ref name="pmid8583243">{{cite journal| author=Carney ME, O'Reilly RC, Sholevar B, Buiakova OI, Lowry LD, Keane WM et al.| title=Expression of the human Achaete-scute 1 gene in olfactory neuroblastoma (esthesioneuroblastoma). | journal=J Neurooncol | year= 1995 | volume= 26 | issue= 1 | pages= 35-43 | pmid=8583243 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=8583243  }} </ref>


==Pathophysiology==
==Pathophysiology==
==Gross Pathology==
===Gross Pathology===
Arises from olfactory mucosa - upper nasal cavity
*On gross examination, biopsy material from olfactory neuroblastoma is soft and hemorrhagic.
==Microscopic Pathology==
*Resection specimens may show a polypoid appearance.
*Small round (blue) cell tumour with:
*The vascular supply of the tumor is rich and fragile, accounting for the hemorrhagic gross appearance.
**Stippled chromatin.
===Microscopic Pathology===
**High NC ratio.
*[[Olfactory]] [[neuroblastomas]] are of neural crest cell origin. They are multilobulated pink-grey tumors.  
*+/-Flexner-Wintersteiner rosette - rosette with empty centre (donut hole).
*On microscopic histopathologic analysis, there is variable differentiation, from well formed neural tissue to undifferentiated neuroblasts with pseudorosette formation.<ref name="radio"> Esthesioneuroblastoma. Radiopedia(2015) http://radiopaedia.org/articles/olfactory-neuroblastoma Accessed on January 25, 2016</ref><ref name="librepathology">  Esthesioneuroblastoma. Libre pathology(2015) http://librepathology.org/wiki/index.php/Olfactory_neuroblastoma Accessed on January 25, 2015</ref>
*+/-Fibrillary, eosinophilic material (neuropil-like)
*Microscopically, the tumor grows beneath the surface respiratory epithelium and may produce focal ulceration.
Olfactory neuroblastomas are of neural crest cell origin. They are mulilobulated pink-grey tumors.
*Esthesioneuroblastomas (ENBs) can display various histologic presentations.
Histology demonstrates variable differentiation, from well formed neural tissue to undifferentiated neuroblasts with pseudorosette formation 2. It has been suggested that olfactory neuroblastoma is actually part of the Ewing sarcoma group of tumors, rather than being related to neuroblastoma.  
**The hallmark of well-differentiated esthesioneuroblastoma is the arrangement of cells into rosettes or pseudorosettes.
**True rosettes (Flexner-Wintersteiner rosettes) are a ring of columnar cells circumscribing a central oval-to-round space. They appear clear on traditional pathologic sections.
**Pseudorosettes (Homer-Wright rosettes) are characterized by a looser arrangement and the presence of fibrillary material within the lumen.


Olfactory neuroblastomas are of neural crest cell origin 1. They are mulilobulated pink-grey tumours.
*In low-grade or well-differentiated lesions, the growth pattern is lobulated with transitions into sheets or discrete nests of [[tumor]] cells, which are small and round with high nuclear cytoplasmic ratios.<ref name="pmid8630875">{{cite journal| author=Hirose T, Scheithauer BW, Lopes MB, Gerber HA, Altermatt HJ, Harner SG et al.| title=Olfactory neuroblastoma. An immunohistochemical, ultrastructural, and flow cytometric study. | journal=Cancer | year= 1995 | volume= 76 | issue= 1 | pages= 4-19 | pmid=8630875 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=8630875  }} </ref><ref name=hhh>Hyams, V. J. (1988). Tumors of the upper respiratory tract and ear. Washington, D.C.: Armed Forces Institute of Pathology.</ref>
*In well-differentiated tumors, the nuclei show uniform [[chromatin]] distribution with small unremarkable [[nucleoli]]. The nuclei become progressively more pleomorphic, with prominent nucleoli and coarse chromatin clumping, with increasing tumor grade. The stroma in well-differentiated tumors is distinctly fibrillary, reflecting the neuronal processes made by the tumor cells. This stroma decreases in quantity as the tumor becomes less well-differentiated. Mitoses and areas of [[necrosis]] also become more frequent with increasing tumor grade.
*In one-half of olfactory [[neuroblastomas]], Homer Wright pseudorosettes, which are composed of tumor cells surrounding a center of pink fibrillary material are seen.
*In higher grade tumors, true (Flexner type) rosettes, composed of tumor cells surrounding a central lumen are seen.
*Vascular or [[lymphatic]] invasion, [[necrosis]], and dystrophic calcification are more common with increasing tumor grade.
*A few admixed ganglion cells may be present, on rare instances.
*Electron microscopy of olfactory neuroblastomas demonstrates numerous axonal-type cytoplasmic processes, which contain [[neurotubules]], [[neurofilaments]], and dense-core neurosecretory granules (100 to 200 nm in diameter). The S100 immunoreactivity corresponds to [[Schwann cells]] enveloping axonal processes and cell bodies.<ref name="pmid8630875">{{cite journal| author=Hirose T, Scheithauer BW, Lopes MB, Gerber HA, Altermatt HJ, Harner SG et al.| title=Olfactory neuroblastoma. An immunohistochemical, ultrastructural, and flow cytometric study. | journal=Cancer | year= 1995 | volume= 76 | issue= 1 | pages= 4-19 | pmid=8630875 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=8630875  }} </ref><ref name=hhh>Hyams, V. J. (1988). Tumors of the upper respiratory tract and ear. Washington, D.C.: Armed Forces Institute of Pathology.</ref>


Histology demonstrates variable differentiation, from well formed neural tissue to undifferentiated neuroblasts with pseudorosette formation 2. It has been suggested that olfactory neuroblastoma is actually part of the Ewing sarcoma group of tumours, rather than being related to neuroblastoma
==Genetics==
*A tool called array comparative genomic hybridization was applied to the analysis of esthesioneuroblastomas. Although many alterations were identified by this study, [[chromosomal]] gains in ''7q11'' and ''20q'' and deletions in ''2q'', ''5q'', ''6p'', ''6q'', and ''18q'' have been confirmed by at least two other studies.
*Although still investigational, the demonstration of human achaete-scute homologue ''HASH1'' gene expression could become the diagnostic procedure of choice. The ''HASH1'' [[gene]] is expressed in immature olfactory cells and is involved in olfactory neuronal differentiation; therefore, it could be useful in distinguishing esthesioneuroblastoma from other poorly differentiated small blue cell tumors.<ref name="pmid18408657">{{cite journal| author=Guled M, Myllykangas S, Frierson HF, Mills SE, Knuutila S, Stelow EB| title=Array comparative genomic hybridization analysis of olfactory neuroblastoma. | journal=Mod Pathol | year= 2008 | volume= 21 | issue= 6 | pages= 770-8 | pmid=18408657 | doi=10.1038/modpathol.2008.57 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=18408657  }} </ref><ref name="pmid15272537">{{cite journal| author=Mhawech P, Berczy M, Assaly M, Herrmann F, Bouzourene H, Allal AS et al.| title=Human achaete-scute homologue (hASH1) mRNA level as a diagnostic marker to distinguish esthesioneuroblastoma from poorly differentiated tumors arising in the sinonasal tract. | journal=Am J Clin Pathol | year= 2004 | volume= 122 | issue= 1 | pages= 100-5 | pmid=15272537 | doi=10.1309/QD0K-9Q1J-BH6B-5GQQ | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15272537  }} </ref><ref name="pmid8583243">{{cite journal| author=Carney ME, O'Reilly RC, Sholevar B, Buiakova OI, Lowry LD, Keane WM et al.| title=Expression of the human Achaete-scute 1 gene in olfactory neuroblastoma (esthesioneuroblastoma). | journal=J Neurooncol | year= 1995 | volume= 26 | issue= 1 | pages= 35-43 | pmid=8583243 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=8583243  }} </ref>


On gross examination, biopsy material from olfactory neuroblastoma is soft and hemorrhagic. Resection specimens may show a polypoid appearance. Microscopically, the tumor grows beneath the surface respiratory epithelium and may produce focal ulceration. The vascular supply is rich and fragile, accounting for the hemorrhagic gross appearance.


In low-grade (well-differentiated) lesions, the growth pattern is lobulated with transitions into sheets or discrete nests of tumor cells, which are small and round with high nuclear cytoplasmic ratios (picture 1) [21,22]. In well-differentiated tumors, the nuclei show uniform chromatin distribution with small inconspicuous nucleoli. The nuclei become progressively more pleomorphic, with coarse chromatin clumping and prominent nucleoli, with increasing tumor grade. The stroma in well-differentiated tumors is distinctly fibrillary, reflecting the neuronal (axonal) processes made by the tumor cells. This stroma decreases in quantity as the tumor becomes less well-differentiated. Mitoses and areas of necrosis also become more frequent with increasing tumor grade.
The Hyams histologic grading system grades tumors from I to IV based upon pathologic features such as mitotic activity and necrosis.<ref name=hhh>Hyams, V. J. (1988). Tumors of the upper respiratory tract and ear. Washington, D.C.: Armed Forces Institute of Pathology.</ref>
 
Homer Wright pseudorosettes, which are composed of tumor cells surrounding a center of pink fibrillary material, are seen in one-half of olfactory neuroblastomas; true (Flexner type) rosettes, composed of tumor cells surrounding a central lumen, are best seen in higher grade tumors. Necrosis, dystrophic calcification, and vascular or lymphatic invasion are more common with increasing tumor grade. In rare instances, a few admixed ganglion cells may be present. Electron microscopy of olfactory neuroblastomas demonstrates numerous axonal-type cytoplasmic processes, which contain neurofilaments, neurotubules, and dense-core neurosecretory granules (100 to 200 nm in diameter) [21,22]. The S100 immunoreactivity corresponds to Schwann cells enveloping cell bodies and axonal processes (see 'Differential diagnosis' below).
 
The Hyams histologic grading system grades tumors from I to IV based upon pathologic features such as mitotic activity and necrosis [21].
 
●Grade I tumors are characterized by a prominent fibrillary matrix, tumor cells with uniform nuclei, absent mitotic activity, and necrosis.
●Grade II tumors have some fibrillary matrix and exhibit moderate nuclear pleomorphism with some mitotic activity. There is no necrosis.
●Grade III tumors have minimal fibrillary matrix and Flexner type rosettes are present. There is more prominent mitotic activity and nuclear pleomorphism, and some necrosis may be seen.
●Grade IV tumors have no fibrillary matrix or rosettes and show marked nuclear pleomorphism and increased mitotic activity with frequent necrosis.
Most studies have found a correlation between Hyams grade and prognosis [13,17,21,23]. In a meta-analysis that included five studies in which lesions were graded histologically, the mean five-year survival was 56 percent for those with low-grade lesions (Hyams I and II) versus 20 percent for those with high-grade lesions (Hyams III and IV) [23]. However, a SEER study of 281 patients treated from 1973 to 2010 showed that patients with grade I and II tumors had a 10-year overall survival rate of 67 percent and those with high grade tumors (III and IV) had a 10-year overall survival rate of 34 percent. For high-grade tumors, multivariate analysis showed Kadish stage predicted for worse disease-specific survival and radiation independently predicted for improved disease-specific survival (B-Tajudden).


{| style="border: 0px; font-size: 90%; margin: 3px; width: 600px" align=center
{| style="border: 0px; font-size: 90%; margin: 3px; width: 600px" align=center
Line 43: Line 43:
:Grade I
:Grade I
| style="padding: 5px 5px; background: #F5F5F5;" |
| style="padding: 5px 5px; background: #F5F5F5;" |
*Grade I tumors are characterized by a prominent fibrillary matrix, tumor cells with uniform nuclei, absent mitotic activity, and necrosis.
*Grade I tumors are characterized by a prominent fibrillary matrix, tumor cells with uniform nuclei, absent mitotic activity, and [[necrosis]].
|-
|-
| style="padding: 5px 5px; background: #DCDCDC; font-weight: bold" |
| style="padding: 5px 5px; background: #DCDCDC; font-weight: bold" |
:Grade II
:Grade II
| style="padding: 5px 5px; background: #F5F5F5;" |
| style="padding: 5px 5px; background: #F5F5F5;" |
*Grade II tumors have some fibrillary matrix and exhibit moderate nuclear pleomorphism with son=me mitotic activity. There is no necrosis
*Grade II tumors have some fibrillary matrix and exhibit moderate nuclear pleomorphism with some mitotic activity. There is no [[necrosis]].
|-
|-
| style="padding: 5px 5px; background: #DCDCDC; font-weight: bold" |
| style="padding: 5px 5px; background: #DCDCDC; font-weight: bold" |
:Grade III
:Grade III
| style="padding: 5px 5px; background: #F5F5F5;" |
| style="padding: 5px 5px; background: #F5F5F5;" |
*Grade III tumors have minimal fibrillary matrix and Flexner type rosettes are present. There is more prominent mitotic activity and nuclear pleomorphism, and some necrosis may be seen
*Grade III tumors have minimal fibrillary matrix and Flexner type rosettes are present. There is more prominent mitotic activity and nuclear pleomorphism, and some [[necrosis]] may be seen.
|-
|-
| style="padding: 5px 5px; background: #DCDCDC;font-weight: bold" |
| style="padding: 5px 5px; background: #DCDCDC;font-weight: bold" |
:Grade IV
:Grade IV
| style="padding: 5px 5px; background: #F5F5F5;" |
| style="padding: 5px 5px; background: #F5F5F5;" |
*Grade IV tumors have no fibrillary matrix or rosettes and show marked nuclear pleomorphism and increased mitotic activity with frequent necrosis
*Grade IV tumors have no fibrillary matrix or rosettes and show marked nuclear pleomorphism and increased mitotic activity with frequent [[necrosis]].
|-
|-
|}
|}


 
The various features of histopathological grading according to Hyams is shown below in a tabular form:<ref name=hhh>Hyams, V. J. (1988). Tumors of the upper respiratory tract and ear. Washington, D.C.: Armed Forces Institute of Pathology.</ref>
{| style="border: 0px; font-size: 90%; margin: 3px; width: 600px" align=center
|valign=top|
|+
! style="background: #4479BA; width: 200px;" | {{fontcolor|#FFF|Grade}}
! style="background: #4479BA; width: 400px;" | {{fontcolor|#FFF|Mitotic Index}}
! style="background: #4479BA; width: 400px;" | {{fontcolor|#FFF|Nuclear Polymorphism}}
! style="background: #4479BA; width: 400px;" | {{fontcolor|#FFF|Fibrillary Matrix}}
! style="background: #4479BA; width: 400px;" | {{fontcolor|#FFF|Rosettes}}
! style="background: #4479BA; width: 400px;" | {{fontcolor|#FFF|Necrosis}}
! style="background: #4479BA; width: 400px;" | {{fontcolor|#FFF|Lobular Architecture Preservation}}
|-
| style="padding: 5px 5px; background: #DCDCDC; font-weight: bold" |
:Grade I
| style="padding: 5px 5px; background: #F5F5F5;" |
Zero
| style="padding: 5px 5px; background: #F5F5F5;" |
None
| style="padding: 5px 5px; background: #F5F5F5;" |
Prominent
| style="padding: 5px 5px; background: #F5F5F5;" |
Homer Wright Rosettes
| style="padding: 5px 5px; background: #F5F5F5;" |
None
| style="padding: 5px 5px; background: #F5F5F5;" |
+
|-
| style="padding: 5px 5px; background: #DCDCDC; font-weight: bold" |
:Grade II
| style="padding: 5px 5px; background: #F5F5F5;" |
Low
| style="padding: 5px 5px; background: #F5F5F5;" |
Low
| style="padding: 5px 5px; background: #F5F5F5;" |
Present
| style="padding: 5px 5px; background: #F5F5F5;" |
Homer Wright Rosettes
| style="padding: 5px 5px; background: #F5F5F5;" |
None
| style="padding: 5px 5px; background: #F5F5F5;" |
+
|-
| style="padding: 5px 5px; background: #DCDCDC; font-weight: bold" |
:Grade III
| style="padding: 5px 5px; background: #F5F5F5;" |
Moderate
| style="padding: 5px 5px; background: #F5F5F5;" |
Moderate
| style="padding: 5px 5px; background: #F5F5F5;" |
Low
| style="padding: 5px 5px; background: #F5F5F5;" |
Flexner-Wintersteiner rosettes
| style="padding: 5px 5px; background: #F5F5F5;" |
Rare
| style="padding: 5px 5px; background: #F5F5F5;" |
+/-
|-
| style="padding: 5px 5px; background: #DCDCDC;font-weight: bold" |
:Grade IV
| style="padding: 5px 5px; background: #F5F5F5;" |
High
| style="padding: 5px 5px; background: #F5F5F5;" |
High
| style="padding: 5px 5px; background: #F5F5F5;" |
Absent
| style="padding: 5px 5px; background: #F5F5F5;" |
None
| style="padding: 5px 5px; background: #F5F5F5;" |
Frequent
| style="padding: 5px 5px; background: #F5F5F5;" |
+/-
|-
|}
===Associated Conditions===
===Associated Conditions===
* Associated with [[Trisomy 8]].
*Esthesioneuroblastoma may be associated with [[Trisomy 8]].


==References==
==References==
{{Reflist|2}}
{{Reflist|2}}
{{Central nervous system tumors}}


[[Category:Disease]]
[[Category:Disease]]
Line 75: Line 145:
[[Category:neurology]]
[[Category:neurology]]
[[Category:Rhinology]]
[[Category:Rhinology]]
[[Category:Needs content]]


{{WH}}
{{WH}}
{{WS}}
{{WS}}
[[Category:Up-To-Date]]
[[Category:Oncology]]
[[Category:Medicine]]
[[Category:Neurology]]
[[Category:Neurosurgery]]

Latest revision as of 23:18, 26 November 2017

Esthesioneuroblastoma Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Esthesioneuroblastoma from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

Staging

History and Symptoms

Physical Examination

Laboratory Findings

CT

MRI

Other Imaging Findings

Other Diagnostic Studies

Treatment

Medical Therapy

Surgery

Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Esthesioneuroblastoma pathophysiology On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Esthesioneuroblastoma pathophysiology

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Esthesioneuroblastoma pathophysiology

CDC on Esthesioneuroblastoma pathophysiology

Esthesioneuroblastoma pathophysiology in the news

Blogs on Esthesioneuroblastoma pathophysiology

Directions to Hospitals Treating Esthesioneuroblastoma

Risk calculators and risk factors for Esthesioneuroblastoma pathophysiology

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Simrat Sarai, M.D. [2]

Overview

Genetic mutations involved in the pathogenesis of esthesioneuroblastoma include chromosomal gains in 7q11 and 20q and deletions in 2q, 5q, 6p, 6q, and 18q. On gross pathology, a soft, hemorrhagic, polypoid appearance, and rich, fragile vascular supply are characteristic findings of esthesioneuroblastoma. On microscopic histopathological analysis, arrangements of cells into rosettes or pseudorosettes are characteristic findings of esthesioneuroblastoma.[1][2][3][4][5][6][7]

Pathophysiology

Gross Pathology

  • On gross examination, biopsy material from olfactory neuroblastoma is soft and hemorrhagic.
  • Resection specimens may show a polypoid appearance.
  • The vascular supply of the tumor is rich and fragile, accounting for the hemorrhagic gross appearance.

Microscopic Pathology

  • Olfactory neuroblastomas are of neural crest cell origin. They are multilobulated pink-grey tumors.
  • On microscopic histopathologic analysis, there is variable differentiation, from well formed neural tissue to undifferentiated neuroblasts with pseudorosette formation.[1][2]
  • Microscopically, the tumor grows beneath the surface respiratory epithelium and may produce focal ulceration.
  • Esthesioneuroblastomas (ENBs) can display various histologic presentations.
    • The hallmark of well-differentiated esthesioneuroblastoma is the arrangement of cells into rosettes or pseudorosettes.
    • True rosettes (Flexner-Wintersteiner rosettes) are a ring of columnar cells circumscribing a central oval-to-round space. They appear clear on traditional pathologic sections.
    • Pseudorosettes (Homer-Wright rosettes) are characterized by a looser arrangement and the presence of fibrillary material within the lumen.
  • In low-grade or well-differentiated lesions, the growth pattern is lobulated with transitions into sheets or discrete nests of tumor cells, which are small and round with high nuclear cytoplasmic ratios.[4][8]
  • In well-differentiated tumors, the nuclei show uniform chromatin distribution with small unremarkable nucleoli. The nuclei become progressively more pleomorphic, with prominent nucleoli and coarse chromatin clumping, with increasing tumor grade. The stroma in well-differentiated tumors is distinctly fibrillary, reflecting the neuronal processes made by the tumor cells. This stroma decreases in quantity as the tumor becomes less well-differentiated. Mitoses and areas of necrosis also become more frequent with increasing tumor grade.
  • In one-half of olfactory neuroblastomas, Homer Wright pseudorosettes, which are composed of tumor cells surrounding a center of pink fibrillary material are seen.
  • In higher grade tumors, true (Flexner type) rosettes, composed of tumor cells surrounding a central lumen are seen.
  • Vascular or lymphatic invasion, necrosis, and dystrophic calcification are more common with increasing tumor grade.
  • A few admixed ganglion cells may be present, on rare instances.
  • Electron microscopy of olfactory neuroblastomas demonstrates numerous axonal-type cytoplasmic processes, which contain neurotubules, neurofilaments, and dense-core neurosecretory granules (100 to 200 nm in diameter). The S100 immunoreactivity corresponds to Schwann cells enveloping axonal processes and cell bodies.[4][8]

Genetics

  • A tool called array comparative genomic hybridization was applied to the analysis of esthesioneuroblastomas. Although many alterations were identified by this study, chromosomal gains in 7q11 and 20q and deletions in 2q, 5q, 6p, 6q, and 18q have been confirmed by at least two other studies.
  • Although still investigational, the demonstration of human achaete-scute homologue HASH1 gene expression could become the diagnostic procedure of choice. The HASH1 gene is expressed in immature olfactory cells and is involved in olfactory neuronal differentiation; therefore, it could be useful in distinguishing esthesioneuroblastoma from other poorly differentiated small blue cell tumors.[5][6][7]


The Hyams histologic grading system grades tumors from I to IV based upon pathologic features such as mitotic activity and necrosis.[8]

Grade Features
Grade I
  • Grade I tumors are characterized by a prominent fibrillary matrix, tumor cells with uniform nuclei, absent mitotic activity, and necrosis.
Grade II
  • Grade II tumors have some fibrillary matrix and exhibit moderate nuclear pleomorphism with some mitotic activity. There is no necrosis.
Grade III
  • Grade III tumors have minimal fibrillary matrix and Flexner type rosettes are present. There is more prominent mitotic activity and nuclear pleomorphism, and some necrosis may be seen.
Grade IV
  • Grade IV tumors have no fibrillary matrix or rosettes and show marked nuclear pleomorphism and increased mitotic activity with frequent necrosis.

The various features of histopathological grading according to Hyams is shown below in a tabular form:[8]

Grade Mitotic Index Nuclear Polymorphism Fibrillary Matrix Rosettes Necrosis Lobular Architecture Preservation
Grade I

Zero

None

Prominent

Homer Wright Rosettes

None

+

Grade II

Low

Low

Present

Homer Wright Rosettes

None

+

Grade III

Moderate

Moderate

Low

Flexner-Wintersteiner rosettes

Rare

+/-

Grade IV

High

High

Absent

None

Frequent

+/-

Associated Conditions

  • Esthesioneuroblastoma may be associated with Trisomy 8.

References

  1. ↑ 1.0 1.1 Esthesioneuroblastoma. Radiopedia(2015) http://radiopaedia.org/articles/olfactory-neuroblastoma Accessed on January 25, 2016
  2. ↑ 2.0 2.1 Esthesioneuroblastoma. Libre pathology(2015) http://librepathology.org/wiki/index.php/Olfactory_neuroblastoma Accessed on January 25, 2015
  3. ↑ Hyams, V. J. (1988). Tumors of the upper respiratory tract and ear. Washington, D.C.: Armed Forces Institute of Pathology.
  4. ↑ 4.0 4.1 4.2 Hirose T, Scheithauer BW, Lopes MB, Gerber HA, Altermatt HJ, Harner SG; et al. (1995). "Olfactory neuroblastoma. An immunohistochemical, ultrastructural, and flow cytometric study". Cancer. 76 (1): 4–19. PMID 8630875.
  5. ↑ 5.0 5.1 Guled M, Myllykangas S, Frierson HF, Mills SE, Knuutila S, Stelow EB (2008). "Array comparative genomic hybridization analysis of olfactory neuroblastoma". Mod Pathol. 21 (6): 770–8. doi:10.1038/modpathol.2008.57. PMID 18408657.
  6. ↑ 6.0 6.1 Mhawech P, Berczy M, Assaly M, Herrmann F, Bouzourene H, Allal AS; et al. (2004). "Human achaete-scute homologue (hASH1) mRNA level as a diagnostic marker to distinguish esthesioneuroblastoma from poorly differentiated tumors arising in the sinonasal tract". Am J Clin Pathol. 122 (1): 100–5. doi:10.1309/QD0K-9Q1J-BH6B-5GQQ. PMID 15272537.
  7. ↑ 7.0 7.1 Carney ME, O'Reilly RC, Sholevar B, Buiakova OI, Lowry LD, Keane WM; et al. (1995). "Expression of the human Achaete-scute 1 gene in olfactory neuroblastoma (esthesioneuroblastoma)". J Neurooncol. 26 (1): 35–43. PMID 8583243.
  8. ↑ 8.0 8.1 8.2 8.3 Hyams, V. J. (1988). Tumors of the upper respiratory tract and ear. Washington, D.C.: Armed Forces Institute of Pathology.

Template:WH Template:WS

Retrieved from "https://www.wikidoc.org/index.php?title=Esthesioneuroblastoma_pathophysiology&oldid=1393541"