Colon polyps pathophysiology: Difference between revisions

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==Overview==
==Overview==
The exact pathogenesis of [disease name] is not fully understood.
Any form of unregulated growth in the [[Colon (anatomy)|colon]] may cause polyps. The exact etiology is unclear. However, risk factors may contribute to the formation of polyps. There are four different types of polyps including [[Inflammation|inflammatory]], [[Hamartoma|hamartomatous]], serrated, and adenomatous polyps, which have different [[pathogenesis]]. [[Inflammation|Inflammatory]] polyps are non-neoplastic polyps that occur following [[Intestine|intestinal]] [[inflammation]], [[Infection|infections]], or [[ischemia]]. [[Hamartoma|Hamartomatous]] polyp is an overgrowth of mature [[Cell (biology)|cells]] and [[connective tissue]] elements including [[smooth muscle]], [[lamina propria]], and [[cartilage]], and [[fat]]. They are covered by a hypertrophic [[epithelium]]. Serrated polyps are different [[Polyp|polyps]] which have variable [[Malignant|malignant potential]]. They include [[Hyperplasia|hyperplastic]], sessile serrated and traditional serrated polyps. [[Hyperplasia|Hyperplastic]] polyps are the most common [[Polyp|polyps]]. [[Hyperplasia|Hyperplastic]] polyp is infolding of the [[Crypt (anatomy)|crypt]] [[epithelium]] that forms serration or saw-toothed appearance. Sessile serrated polyps are flask-shaped crypts, with dilatation and branching but not pedunculated. Traditional serrated adenomas are serrated polyps that are protuberant and pedunculated, which are located in left [[Colon (anatomy)|colon]]. Traditional adenoma also known as conventional [[Polyp|polyps]], are developed throughout the [[Colon (anatomy)|colon]]. They are the most prevalent polyps that have [[malignant]] potential.
 
OR
 
It is thought that [disease name] is the result of / is mediated by / is produced by / is caused by either [hypothesis 1], [hypothesis 2], or [hypothesis 3].
 
OR
 
[Pathogen name] is usually transmitted via the [transmission route] route to the human host.
 
OR
 
Following transmission/ingestion, the [pathogen] uses the [entry site] to invade the [cell name] cell.
 
OR
 
 
[Disease or malignancy name] arises from [cell name]s, which are [cell type] cells that are normally involved in [function of cells].
 
OR
 
The progression to [disease name] usually involves the [molecular pathway].
 
OR
 
The pathophysiology of [disease/malignancy] depends on the histological subtype.


==Pathophysiology==
==Pathophysiology==
*Any form of unregulated growth in the [[Colon (anatomy)|colon]] may cause polyps. The exact etiology is unclear. However, risk factors may contribute to the formation of polyps.<ref name="pmid18314605">{{cite journal |vauthors=Rüschoff J, Aust D, Hartmann A |title=[Colorectal serrated adenoma: diagnostic criteria and clinical implications] |language=German |journal=Verh Dtsch Ges Pathol |volume=91 |issue= |pages=119–25 |year=2007 |pmid=18314605 |doi= |url=}}</ref><ref name="ShussmanWexner2014">{{cite journal|last1=Shussman|first1=N.|last2=Wexner|first2=S. D.|title=Colorectal polyps and polyposis syndromes|journal=Gastroenterology Report|volume=2|issue=1|year=2014|pages=1–15|issn=2052-0034|doi=10.1093/gastro/got041}}</ref><ref name="SinghZorrón Cheng Tao Pu2016">{{cite journal|last1=Singh|first1=Rajvinder|last2=Zorrón Cheng Tao Pu|first2=Leonardo|last3=Koay|first3=Doreen|last4=Burt|first4=Alastair|title=Sessile serrated adenoma/polyps: Where are we at in 2016?|journal=World Journal of Gastroenterology|volume=22|issue=34|year=2016|pages=7754|issn=1007-9327|doi=10.3748/wjg.v22.i34.7754}}</ref><ref name="KahiVemulapalli2015">{{cite journal|last1=Kahi|first1=Charles J.|last2=Vemulapalli|first2=Krishna C.|last3=Snover|first3=Dale C.|last4=Abdel Jawad|first4=Khaled H.|last5=Cummings|first5=Oscar W.|last6=Rex|first6=Douglas K.|title=Findings in the Distal Colorectum Are Not Associated With Proximal Advanced Serrated Lesions|journal=Clinical Gastroenterology and Hepatology|volume=13|issue=2|year=2015|pages=345–351|issn=15423565|doi=10.1016/j.cgh.2014.07.044}}</ref>
*There are four different types of polyps including [[Inflammation|inflammatory]], [[Hamartoma|hamartomatous]], serrated, and adenomatous polyps, which have different [[pathogenesis]].
*The [[pathophysiology]] of colon polyps depends on the [[Histology|histological]] type.
{{#ev:youtube|oJU7CokNLZY}}
{{#ev:youtube|7n5EnaLOV54}}
==== [[Inflammation|Inflammatory]] polyps ====
*[[Inflammation|Inflammatory]] polyps are non-neoplastic polyps that occur following [[Intestine|intestinal]] [[inflammation]], [[Infection|infections]], or [[ischemia]].<ref name="ShussmanWexner2014">{{cite journal|last1=Shussman|first1=N.|last2=Wexner|first2=S. D.|title=Colorectal polyps and polyposis syndromes|journal=Gastroenterology Report|volume=2|issue=1|year=2014|pages=1–15|issn=2052-0034|doi=10.1093/gastro/got041}}</ref><ref name="pmid17516746">{{cite journal |vauthors=Li SC, Burgart L |title=Histopathology of serrated adenoma, its variants, and differentiation from conventional adenomatous and hyperplastic polyps |journal=Arch. Pathol. Lab. Med. |volume=131 |issue=3 |pages=440–5 |year=2007 |pmid=17516746 |doi=10.1043/1543-2165(2007)131[440:HOSAIV]2.0.CO;2 |url=}}</ref>
*They mostly occur in patients with [[inflammatory bowel disease]], mainly [[ulcerative colitis]].
*They are considered as [[Pseudopolyp|pseudopolyps]] which contain [[Inflammation|inflammatory]] infiltrations with distorted [[Mucous membrane|mucosa]].
*It had no [[malignant]] potential. However, it is recommended to [[biopsy]] the lesion and surrounding [[Mucous membrane|mucosa]].
*[[Microscopic]] pathology of [[biopsy]] shows mixture of normal, [[Ulcer|ulcerated]], and regenerating [[Mucous membrane|mucosa]] which is surrounded by areas of [[Mucous membrane|mucosal]] loss.


===Pathogenesis===
==== [[Hamartoma|Hamartomatous]] polyps ====
*The exact pathogenesis of [disease name] is not fully understood.
* [[Hamartoma|Hamartomatous]] polyp is an overgrowth of mature [[Cell (biology)|cells]] and [[connective tissue]] elements including [[smooth muscle]], [[lamina propria]], and [[cartilage]], and [[fat]]. They are covered by a hypertrophic [[epithelium]].<ref name="pmid17768394">{{cite journal |vauthors=Zbuk KM, Eng C |title=Hamartomatous polyposis syndromes |journal=Nat Clin Pract Gastroenterol Hepatol |volume=4 |issue=9 |pages=492–502 |year=2007 |pmid=17768394 |doi=10.1038/ncpgasthep0902 |url=}}</ref>
OR
* They might be [[pedunculated]], [[Inflammation|inflamed]], or smooth polyps which are [[solitary]] or multiple.
*It is thought that [disease name] is the result of / is mediated by / is produced by / is caused by either [hypothesis 1], [hypothesis 2], or [hypothesis 3].
* [[Solitary]] [[Hamartoma|hamartomatous]] polyps, also known as juvenile polyps, can present more commonly in younger population.
*[Pathogen name] is usually transmitted via the [transmission route] route to the human host.
* Solitary polyps has no significant risk of [[cancer]]. However, multiple polyps of the colon have a 10% risk of [[Cancer|malignancy]].
*Following transmission/ingestion, the [pathogen] uses the [entry site] to invade the [cell name] cell.
==== Serrated polyps ====
*[Disease or malignancy name] arises from [cell name]s, which are [cell type] cells that are normally involved in [function of cells].
* Serrated polyps are different [[Polyp|polyps]] which have variable [[Malignant|malignant potential]]. They include [[Hyperplasia|hyperplastic]], sessile serrated and traditional serrated polyps. They have various histopathologies and manifestations:
*The progression to [disease name] usually involves the [molecular pathway].
** [[Hyperplasia|Hyperplastic]] polyps are the most common [[Polyp|polyps]].
*The pathophysiology of [disease/malignancy] depends on the histological subtype.
*** They are small outpouching, less than 5 mm, which are located mostly in rectosigmoid area.   
*** [[Hyperplasia|Hyperplastic]] polyp is infolding of the [[Crypt (anatomy)|crypt]] [[epithelium]] that forms serration or saw-toothed appearance.   
*** The molecular basis of this transformation is still unclear. However, it has been attributed to failure of [[apoptosis]].    
*** [[BRAF]] mutations are associated with crypt serration.<ref name="pmid15247181">{{cite journal |vauthors=Kambara T, Simms LA, Whitehall VL, Spring KJ, Wynter CV, Walsh MD, Barker MA, Arnold S, McGivern A, Matsubara N, Tanaka N, Higuchi T, Young J, Jass JR, Leggett BA |title=BRAF mutation is associated with DNA methylation in serrated polyps and cancers of the colorectum |journal=Gut |volume=53 |issue=8 |pages=1137–44 |year=2004 |pmid=15247181 |pmc=1774130 |doi=10.1136/gut.2003.037671 |url=}}</ref> 
*** There are three different subtypes of [[Hyperplasia|hyperplastic]] polyps based on degree of serration and content, including microvesicular type, goblet cell–rich type, and mucin-poor type.   
**    Sessile serrated polyps:
***    They are flask-shaped crypts, with dilatation and branching but not pedunculated.<ref name="BettingtonWalker2013">{{cite journal|last1=Bettington|first1=Mark|last2=Walker|first2=Neal|last3=Clouston|first3=Andrew|last4=Brown|first4=Ian|last5=Leggett|first5=Barbara|last6=Whitehall|first6=Vicki|title=The serrated pathway to colorectal carcinoma: current concepts and challenges|journal=Histopathology|volume=62|issue=3|year=2013|pages=367–386|issn=03090167|doi=10.1111/his.12055}}</ref><ref name="O'ConnellCrockett2017">{{cite journal|last1=O'Connell|first1=Brendon M|last2=Crockett|first2=Seth D|title=The clinical impact of serrated colorectal polyps|journal=Clinical Epidemiology|volume=Volume 9|year=2017|pages=113–125|issn=1179-1349|doi=10.2147/CLEP.S106257}}</ref>
***    Crypts grow along muscularis mucosae and creating inverted T- or L-shaped appearance.
***    Serration happens at the base and bottom of the crypts.  
** Traditional serrated adenomas:
*** They are protuberant and pedunculated [[Polyp|polyps]], less than 1.5 cm, which are located in left [[Colon (anatomy)|colon]].<ref name="pmid17516746">{{cite journal |vauthors=Li SC, Burgart L |title=Histopathology of serrated adenoma, its variants, and differentiation from conventional adenomatous and hyperplastic polyps |journal=Arch. Pathol. Lab. Med. |volume=131 |issue=3 |pages=440–5 |year=2007 |pmid=17516746 |doi=10.1043/1543-2165(2007)131[440:HOSAIV]2.0.CO;2 |url=}}</ref>
*** They have [[Cell biology|cytological]] [[dysplasia]] including [[Cell nucleus|nuclear]] transformation, irregular [[Cell nucleus|nuclear]] polarity, and serration.
*** [[Cell biology|Cytological]] [[dysplasia]] causes crypts that are irregular and branching.
==== Adenomatous polyps ====
*Traditional adenoma also known as conventional [[Polyp|polyps]], are developed throughout the [[Colon (anatomy)|colon]].
*They are the most prevalent polyps that have [[malignant]] potential.
*They have different gross appearances including [[pedunculated]], [[sessile]], flat, or depressed.
*They might have different [[Histopathology|histopathologies]] including tubular, villous, or tubulovillous.


==Genetics==
==Genetics==
*[Disease name] is transmitted in [mode of genetic transmission] pattern.
*The development of colon polyps is the result of multiple [[Mutation|genetic mutations]].
*Genes involved in the pathogenesis of [disease name] include [gene1], [gene2], and [gene3].
*Genetic mutations might cause [[Heredity|hereditary]] polyps disorders.
*The development of [disease name] is the result of multiple genetic mutations.
 
==== '''[[Familial adenomatous polyposis]] ([[FAP]])''' ====
* FAP is due to mutations in the following genes:
** ''[[APC (gene)|APC]]'' gene, which is located on [[chromosome]] 5 in band q21 or band q22 (5q21-q22).
** ''[[MUTYH]]'' gene, which is located on chromosome 1 between bands p34.2 and p32.1 (5p34.3-p32.1).
** MYH-associated polyposis (MAP) is caused by mutations in the MYH gene.
'''[[Peutz-Jeghers syndrome]]'''
* It is thought that Peutz-Jeghers syndrome is the result of [[Deletion (genetics)|deletion]] or [[Deletion (genetics)|partial deletion]] of [[STK11]] (LBK1) gene, located on [[chromosome]] 19p13.3.
'''[[Gardner's syndrome]]'''
* It is caused by [[mutation]] in the [[APC gene]] located in [[chromosome]] 5q21 (band q21 on chromosome 5). 
'''Serrated polyposis syndrome'''
* They develop multiple serrated adenomatous polyps in the upper part of the colon.


==Associated Conditions==
==== Familial juvenile polyposis ====
*It is an autosomal dominant disorder. 
*It increases risk of colorectal cancer.
*It has extra-colonic tumors. 
*There has been some association with the following genes:
**SMAD4 on [[Chromosome 18 (human)|chromosome 18]].
**PTEN on [[Chromosome 10 (human)|chromosome 10]].


==Gross Pathology==
==Gross Pathology==
*On gross pathology, [feature1], [feature2], and [feature3] are characteristic findings of [disease name].
*On gross [[pathology]], outpouching, pedunculated or flat lesions are characteristic findings of colon polyps.
 
*On gross [[pathology]], colon polyps may have a short or long stalk.
*The polyp might have hemorrhagic stalk and colon wall with pale ribbon of mucosal covering.
{|
{|
|[[image:Image of resected colon segment with cancer & 4 nearby polyps plus schematic of field defects with sub-clones.jpg|thumb|300 px|Longitudinally opened freshly resected colon segment showing a cancer and four polyps. Plus a schematic diagram indicating a likely field defect (a region of tissue that precedes and predisposes to the development of cancer) in this colon segment. The diagram indicates sub-clones and sub-sub-clones that were precursors to the tumors.
|[[Image:Villous_adenoma_of_the_sigmoid_colon,_gross_pathology.jpg|thumb|left|Villous [[Adenoma]] of the [[Transverse colon]] By http://web2.airmail.net/uthman/specimens/index.html, Public Domain, https://commons.wikimedia.org/w/index.php?curid=840194]]
Source: Wikimedia.org By Bernstein0275 - Own work, CC BY-SA 3.0<ref name="urlFile:Image of resected colon segment with cancer & 4 nearby polyps plus schematic of field defects with sub-clones.jpg - Wikimedia Commons">{{cite web |url=https://commons.wikimedia.org/w/index.php?curid=25453056 |title=File:Image of resected colon segment with cancer & 4 nearby polyps plus schematic of field defects with sub-clones.jpg - Wikimedia Commons |format= |work= |accessdate=}}</ref>
|-
|[[Image:Tvp_enface.jpg|thumb|left|Tubulovillous Polyp of the [[Colon (anatomy)|Colon]] By http://web2.airmail.net/uthman/specimens/index.html, Public Domain, https://commons.wikimedia.org/w/index.php?curid=840172]]
|-
|[[Image:Tubulovillous_polyp_of_the_colon.jpg|thumb|left|Tubulovillous Polyp of the [[Colon (anatomy)|Colon]] By http://web2.airmail.net/uthman/specimens/index.html, Public Domain, https://commons.wikimedia.org/w/index.php?curid=840176]]
|-
|[[Image:Adenomatous_Polyp_of_the_Colon_1.jpg|thumb|left|Adenomatous Polyp of the [[Colon (anatomy)|Colon]] By http://web2.airmail.net/uthman/specimens/index.html, Public Domain, https://commons.wikimedia.org/w/index.php?curid=840154]]
|-
|[[Image:Adenomatous_polyp_of_colon_2.jpg|thumb|left|Adenomatous Polyp of the [[Colon (anatomy)|Colon]] By http://web2.airmail.net/uthman/specimens/index.html, Public Domain, https://commons.wikimedia.org/w/index.php?curid=840157]]
|-
|[[image:Image of resected colon segment with cancer & 4 nearby polyps plus schematic of field defects with sub-clones.jpg|thumb|left|Longitudinally opened freshly resected [[Colon (anatomy)|colon]] segment showing [[cancer]] and four [[Polyp|polyps]]. Plus a schematic diagram indicating a likely field defect (a region of [[Tissue (biology)|tissue]] that precedes and predisposes to the development of [[cancer]]) in this [[Colon (anatomy)|colon]] segment. The diagram indicates sub-clones and sub-sub-clones that were precursors to the [[Tumor|tumors]]. Source: Wikimedia.org By Bernstein0275 - Own work, CC BY-SA 3.0<ref name="urlFile:Image of resected colon segment with cancer & 4 nearby polyps plus schematic of field defects with sub-clones.jpg - Wikimedia Commons">{{cite web |url=https://commons.wikimedia.org/w/index.php?curid=25453056 |title=File:Image of resected colon segment with cancer & 4 nearby polyps plus schematic of field defects with sub-clones.jpg - Wikimedia Commons |format= |work= |accessdate=}}</ref>]]
|-
|[[Image:Colon-Polyp.jpg|thumb|left|Colon polyp on [[Colonoscopy]] By 邱鈺鋒 - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=37027826]]
|-
|[[Image:Endomucosal resection 1.jpg|thumb|left|[[Endoscopy|Endoscopic]] image, 1 of 4, of an endomucosal resection of a sessile colon polyp By The original uploader was Kd4ttc at English Wikipedia - Transferred from en.wikipedia to Commons., CC BY 2.5, https://commons.wikimedia.org/w/index.php?curid=2175689]]
|-
|-
|}
|}


==Microscopic Pathology==
==Microscopic Pathology==
*On microscopic histopathological analysis, [feature1], [feature2], and [feature3] are characteristic findings of [disease name].
*On microscopic [[Histopathology|histopathological]] analysis, serration of the luminal surface and normal [[Cell nucleus|nuclei]] are characteristic findings of hyperplastic polyps.
*On microscopic [[Histopathology|histopathological]] analysis, branched tubular glands are characteristic findings of tubular [[adenoma]].
*On microscopic [[Histopathology|histopathological]] analysis, long finger-like projections are characteristic findings of villous [[adenoma]].
*On microscopic [[Histopathology|histopathological]] analysis, branched and dilated [[Gland|glands]], no [[Cell biology|cytological]] [[atypia]], [[eosinophilic]] [[cytoplasm]], and luminal [[Epithelium|epithelial]] tufting are characteristic findings of sessile serrated [[adenoma]].
[[Image:Hyperplastic_polyp_of_the_colon,_HE.png|thumb|left|Hyperplastic polyp of the [[Colon (anatomy)|Colon]]. By Patho - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=19409502]]
[[Image:Hyperplastic_polyp2.jpg|thumb|left|Micrograph of a [[Colon (anatomy)|colorectal]] hyperplastic polyp. [[H&E stain]]. By Nephron - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=6427545]]
[[Image:Colon_adenoma_(1).jpg|thumb|left|[[Colon (anatomy)|Colon]] [[adenoma]] By No machine-readable author provided. KGH assumed (based on copyright claims). - No machine-readable source provided. Own work assumed (based on copyright claims)., CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=444694]]
<br style="clear:left" />


==References==
==References==
{{Reflist|2}}
{{Reflist|2}}
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{{WH}}
[[Category:Medicine]]
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Latest revision as of 21:01, 29 July 2020

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

Overview

Any form of unregulated growth in the colon may cause polyps. The exact etiology is unclear. However, risk factors may contribute to the formation of polyps. There are four different types of polyps including inflammatory, hamartomatous, serrated, and adenomatous polyps, which have different pathogenesis. Inflammatory polyps are non-neoplastic polyps that occur following intestinal inflammation, infections, or ischemia. Hamartomatous polyp is an overgrowth of mature cells and connective tissue elements including smooth muscle, lamina propria, and cartilage, and fat. They are covered by a hypertrophic epithelium. Serrated polyps are different polyps which have variable malignant potential. They include hyperplastic, sessile serrated and traditional serrated polyps. Hyperplastic polyps are the most common polyps. Hyperplastic polyp is infolding of the crypt epithelium that forms serration or saw-toothed appearance. Sessile serrated polyps are flask-shaped crypts, with dilatation and branching but not pedunculated. Traditional serrated adenomas are serrated polyps that are protuberant and pedunculated, which are located in left colon. Traditional adenoma also known as conventional polyps, are developed throughout the colon. They are the most prevalent polyps that have malignant potential.

Pathophysiology

{{#ev:youtube|oJU7CokNLZY}} {{#ev:youtube|7n5EnaLOV54}}

Inflammatory polyps

Hamartomatous polyps

Serrated polyps

  • Serrated polyps are different polyps which have variable malignant potential. They include hyperplastic, sessile serrated and traditional serrated polyps. They have various histopathologies and manifestations:
    • Hyperplastic polyps are the most common polyps.
      • They are small outpouching, less than 5 mm, which are located mostly in rectosigmoid area.
      • Hyperplastic polyp is infolding of the crypt epithelium that forms serration or saw-toothed appearance.
      • The molecular basis of this transformation is still unclear. However, it has been attributed to failure of apoptosis.
      • BRAF mutations are associated with crypt serration.[7]
      • There are three different subtypes of hyperplastic polyps based on degree of serration and content, including microvesicular type, goblet cell–rich type, and mucin-poor type.
    • Sessile serrated polyps:
      • They are flask-shaped crypts, with dilatation and branching but not pedunculated.[8][9]
      • Crypts grow along muscularis mucosae and creating inverted T- or L-shaped appearance.
      • Serration happens at the base and bottom of the crypts.
    • Traditional serrated adenomas:

Adenomatous polyps

  • Traditional adenoma also known as conventional polyps, are developed throughout the colon.
  • They are the most prevalent polyps that have malignant potential.
  • They have different gross appearances including pedunculated, sessile, flat, or depressed.
  • They might have different histopathologies including tubular, villous, or tubulovillous.

Genetics

  • The development of colon polyps is the result of multiple genetic mutations.
  • Genetic mutations might cause hereditary polyps disorders.

Familial adenomatous polyposis (FAP)

  • FAP is due to mutations in the following genes:
    • APC gene, which is located on chromosome 5 in band q21 or band q22 (5q21-q22).
    • MUTYH gene, which is located on chromosome 1 between bands p34.2 and p32.1 (5p34.3-p32.1).
    • MYH-associated polyposis (MAP) is caused by mutations in the MYH gene.

Peutz-Jeghers syndrome

Gardner's syndrome

Serrated polyposis syndrome

  • They develop multiple serrated adenomatous polyps in the upper part of the colon.

Familial juvenile polyposis

  • It is an autosomal dominant disorder. 
  • It increases risk of colorectal cancer.
  • It has extra-colonic tumors. 
  • There has been some association with the following genes:

Gross Pathology

  • On gross pathology, outpouching, pedunculated or flat lesions are characteristic findings of colon polyps.
  • On gross pathology, colon polyps may have a short or long stalk.
  • The polyp might have hemorrhagic stalk and colon wall with pale ribbon of mucosal covering.
Villous Adenoma of the Transverse colon By http://web2.airmail.net/uthman/specimens/index.html, Public Domain, https://commons.wikimedia.org/w/index.php?curid=840194
Tubulovillous Polyp of the Colon By http://web2.airmail.net/uthman/specimens/index.html, Public Domain, https://commons.wikimedia.org/w/index.php?curid=840172
Tubulovillous Polyp of the Colon By http://web2.airmail.net/uthman/specimens/index.html, Public Domain, https://commons.wikimedia.org/w/index.php?curid=840176
Adenomatous Polyp of the Colon By http://web2.airmail.net/uthman/specimens/index.html, Public Domain, https://commons.wikimedia.org/w/index.php?curid=840154
Adenomatous Polyp of the Colon By http://web2.airmail.net/uthman/specimens/index.html, Public Domain, https://commons.wikimedia.org/w/index.php?curid=840157
Longitudinally opened freshly resected colon segment showing cancer and four polyps. Plus a schematic diagram indicating a likely field defect (a region of tissue that precedes and predisposes to the development of cancer) in this colon segment. The diagram indicates sub-clones and sub-sub-clones that were precursors to the tumors. Source: Wikimedia.org By Bernstein0275 - Own work, CC BY-SA 3.0[10]
Colon polyp on Colonoscopy By 邱鈺鋒 - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=37027826
Endoscopic image, 1 of 4, of an endomucosal resection of a sessile colon polyp By The original uploader was Kd4ttc at English Wikipedia - Transferred from en.wikipedia to Commons., CC BY 2.5, https://commons.wikimedia.org/w/index.php?curid=2175689

Microscopic Pathology

Hyperplastic polyp of the Colon. By Patho - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=19409502
Micrograph of a colorectal hyperplastic polyp. H&E stain. By Nephron - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=6427545
Colon adenoma By No machine-readable author provided. KGH assumed (based on copyright claims). - No machine-readable source provided. Own work assumed (based on copyright claims)., CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=444694


References

  1. ↑ Rüschoff J, Aust D, Hartmann A (2007). "[Colorectal serrated adenoma: diagnostic criteria and clinical implications]". Verh Dtsch Ges Pathol (in German). 91: 119–25. PMID 18314605.
  2. ↑ 2.0 2.1 Shussman, N.; Wexner, S. D. (2014). "Colorectal polyps and polyposis syndromes". Gastroenterology Report. 2 (1): 1–15. doi:10.1093/gastro/got041. ISSN 2052-0034.
  3. ↑ Singh, Rajvinder; Zorrón Cheng Tao Pu, Leonardo; Koay, Doreen; Burt, Alastair (2016). "Sessile serrated adenoma/polyps: Where are we at in 2016?". World Journal of Gastroenterology. 22 (34): 7754. doi:10.3748/wjg.v22.i34.7754. ISSN 1007-9327.
  4. ↑ Kahi, Charles J.; Vemulapalli, Krishna C.; Snover, Dale C.; Abdel Jawad, Khaled H.; Cummings, Oscar W.; Rex, Douglas K. (2015). "Findings in the Distal Colorectum Are Not Associated With Proximal Advanced Serrated Lesions". Clinical Gastroenterology and Hepatology. 13 (2): 345–351. doi:10.1016/j.cgh.2014.07.044. ISSN 1542-3565.
  5. ↑ 5.0 5.1 Li SC, Burgart L (2007). "Histopathology of serrated adenoma, its variants, and differentiation from conventional adenomatous and hyperplastic polyps". Arch. Pathol. Lab. Med. 131 (3): 440–5. doi:10.1043/1543-2165(2007)131[440:HOSAIV]2.0.CO;2. PMID 17516746.
  6. ↑ Zbuk KM, Eng C (2007). "Hamartomatous polyposis syndromes". Nat Clin Pract Gastroenterol Hepatol. 4 (9): 492–502. doi:10.1038/ncpgasthep0902. PMID 17768394.
  7. ↑ Kambara T, Simms LA, Whitehall VL, Spring KJ, Wynter CV, Walsh MD, Barker MA, Arnold S, McGivern A, Matsubara N, Tanaka N, Higuchi T, Young J, Jass JR, Leggett BA (2004). "BRAF mutation is associated with DNA methylation in serrated polyps and cancers of the colorectum". Gut. 53 (8): 1137–44. doi:10.1136/gut.2003.037671. PMC 1774130. PMID 15247181.
  8. ↑ Bettington, Mark; Walker, Neal; Clouston, Andrew; Brown, Ian; Leggett, Barbara; Whitehall, Vicki (2013). "The serrated pathway to colorectal carcinoma: current concepts and challenges". Histopathology. 62 (3): 367–386. doi:10.1111/his.12055. ISSN 0309-0167.
  9. ↑ O'Connell, Brendon M; Crockett, Seth D (2017). "The clinical impact of serrated colorectal polyps". Clinical Epidemiology. Volume 9: 113–125. doi:10.2147/CLEP.S106257. ISSN 1179-1349.
  10. ↑ "File:Image of resected colon segment with cancer & 4 nearby polyps plus schematic of field defects with sub-clones.jpg - Wikimedia Commons".

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