Difference between revisions of "Duodenum"

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[[Image:Duodenumanatomy.jpg|thumb|Schematic of the duodenum. (WC/Luke Guthmann)]]
The '''duodenum''' is the first part of the [[small bowel]] and receives food from the [[stomach]].  It is accessible by EGD (esophagogastroduodenoscopy) and frequently biopsied.   
The '''duodenum''' is the first part of the [[small bowel]] and receives food from the [[stomach]].  It is accessible by EGD (esophagogastroduodenoscopy) and frequently biopsied.   


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===Sign out===
===Sign out===
<pre>
Duodenum, Biopsy:
- Small bowel mucosa and Brunner's glands within normal limits.</pre>
<pre>
Duodenum, Biopsy:
- Small bowel mucosa within normal limits.
</pre>
<pre>
Duodenum, Biopsy:
- Small bowel mucosa within normal limits.
- NEGATIVE for findings suggestive of celiac disease.
</pre>
<pre>
Small Bowel (Duodenum), Biopsy:
- Small bowel mucosa within normal limits.
- NEGATIVE for findings suggestive of celiac disease.
</pre>
====Block letters====
<pre>
<pre>
DUODENUM, BIOPSY:  
DUODENUM, BIOPSY:  
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==Gastric heterotopia of the duodenum==
==Gastric heterotopia of the duodenum==
*[[AKA]] ''heterotopic gastric mucosa''.
*[[AKA]] ''heterotopic gastric mucosa''.
===General===
{{Main|Gastric heterotopia of the duodenum}}
*Common ~15% of cases in one series.<ref name=pmid22295146>{{Cite journal  | last1 = Terada | first1 = T. | title = Pathologic observations of the duodenum in 615 consecutive duodenal specimens: I. benign lesions. | journal = Int J Clin Exp Pathol | volume = 5 | issue = 1 | pages = 46-51 | month =  | year = 2012 | doi =  | PMID = 22295146 }}</ref>
*Probably not related to [[Helicobacter pylori]].<ref name=pmid20656325>{{Cite journal  | last1 = Genta | first1 = RM. | last2 = Kinsey | first2 = RS. | last3 = Singhal | first3 = A. | last4 = Suterwala | first4 = S. | title = Gastric foveolar metaplasia and gastric heterotopia in the duodenum: no evidence of an etiologic role for Helicobacter pylori. | journal = Hum Pathol | volume = 41 | issue = 11 | pages = 1593-600 | month = Nov | year = 2010 | doi = 10.1016/j.humpath.2010.04.010 | PMID = 20656325 }}</ref>
 
===Microscopic===
Features:
#Foveolar epithelium.
#Gastric glands - body-type or antral-type.
 
DDx:
*Foveolar metaplasia.
 
====Images====
www:
*[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3267485/figure/fig03/ Gastric heterotopia (nih.gov)].<ref name=pmid22295146>{{Cite journal  | last1 = Terada | first1 = T. | title = Pathologic observations of the duodenum in 615 consecutive duodenal specimens: I. benign lesions. | journal = Int J Clin Exp Pathol | volume = 5 | issue = 1 | pages = 46-51 | month =  | year = 2012 | doi =  | PMID = 22295146 }}</ref>
 
===Sign out===
<pre>
DUODENUM, BIOPSY:
- SMALL BOWEL MUCOSA AND BRUNNER'S GLANDS WITHIN NORMAL LIMITS.
- GASTRIC HETEROTOPIA, BODY-TYPE MUCOSA.
</pre>


==Celiac sprue==
==Celiac sprue==
*[[AKA]] ''celiac disease''.
{{main|Celiac sprue}}
{{main|Celiac sprue}}
===General===
*Etiology: autoimmune.
====Epidemiology====
*Associated with:
**The skin condition ''[[dermatitis herpetiformis]]''.<ref>TN 2007 D22</ref>
**IgA deficiency - 10-15X more common in celiac disease vs. healthy controls.<ref name=pmid12414763>{{Cite journal  | last1 = Kumar | first1 = V. | last2 = Jarzabek-Chorzelska | first2 = M. | last3 = Sulej | first3 = J. | last4 = Karnewska | first4 = K. | last5 = Farrell | first5 = T. | last6 = Jablonska | first6 = S. | title = Celiac disease and immunoglobulin a deficiency: how effective are the serological methods of diagnosis? | journal = Clin Diagn Lab Immunol | volume = 9 | issue = 6 | pages = 1295-300 | month = Nov | year = 2002 | doi =  | PMID = 12414763 }}</ref>
**Risk factor for ''gastrointestinal T cell lymphoma'' - known as: ''enteropathy-associated T cell lymphoma'' (EATL).
====Clinical====
Treatment:
*Gluten free diet.
**''Mnemonic'': BROW = barley, rye, oats, wheat.
Serologic testing:
*Anti-transglutaminase antibody.
**Alternative test: anti-endomysial antibody.
*IgA -- assoc. with celiac sprue.
===Microscopic===
Features:<ref name=Ref_PBoD843>{{Ref PBoD|843}}</ref>
*Intraepithelial lymphocytes (IELs) - '''key feature'''.
**Should be more pronounced at tips of villi.<ref name=pmid15280404>{{cite journal |author=Biagi F, Luinetti O, Campanella J, ''et al.'' |title=Intraepithelial lymphocytes in the villous tip: do they indicate potential coeliac disease? |journal=J. Clin. Pathol. |volume=57 |issue=8 |pages=835–9 |year=2004 |month=August |pmid=15280404 |pmc=1770380 |doi=10.1136/jcp.2003.013607 |url=}}</ref>
**Criteria for number varies:
*** > 40 IELs / 100 enterocytes (epithelial cells).<ref name=pmid10524652>{{cite journal |author=Oberhuber G, Granditsch G, Vogelsang H |title=The histopathology of coeliac disease: time for a standardized report scheme for pathologists |journal=Eur J Gastroenterol Hepatol |volume=11 |issue=10 |pages=1185–94 |year=1999 |month=October |pmid=10524652 |doi= |url=}}</ref>
*** > 25 IELs / 100 enterocytes (epithelial cells).<ref name=pmid17544877>{{cite journal |author=Corazza GR, Villanacci V, Zambelli C, ''et al.'' |title=Comparison of the interobserver reproducibility with different histologic criteria used in celiac disease |journal=Clin. Gastroenterol. Hepatol. |volume=5 |issue=7 |pages=838–43 |year=2007 |month=July |pmid=17544877 |doi=10.1016/j.cgh.2007.03.019 |url=}}</ref>
*Loss of villi - '''important feature'''.
**Normal duodenal biopsy should have 3 good villi.
*Plasma cells - abundant (weak feature).
*Macrophages.
*Mitosis increased (in the crypts).
*+/-Collagen band (pink material in mucosa) - "Collagenous sprue"; must encompass ~25% of mucosa.
Image:
*[http://commons.wikimedia.org/wiki/File:Coeliac_path.jpg Celiac sprue (WC)].
Notes:
*If you see acute inflammatory cells, i.e. neutrophils, consider Giardiasis and other infectious etiologies.
*Biopsy should consist of 2-3 sites.  In children it is important to sample the duodenal cap, as it is the only affected site in ~10% of cases.
*Flat lesions without IELs are unlikely to be celiac sprue.
*Mucosa erosions are rare in celiac sprue; should prompt consideration of an alternate diagnosis (infection, medications, Crohn's disease).
===Grading===
Rarely done - see ''[[celiac sprue]]'' article.


==Giardiasis==
==Giardiasis==
===General===
{{Main|Giardiasis}}
*Etiology:
**Flagellate protozoan ''Giardia lamblia''.
 
*Treatment
**Antibiotics, e.g. metronidazole (Flagyl).
 
===Gross===
*Diffuse changes.
*May have scattered white spots.<ref name=pmid19906109>{{Cite journal  | last1 = Biyikoğlu | first1 = I. | last2 = Babali | first2 = A. | last3 = Cakal | first3 = B. | last4 = Köklü | first4 = S. | last5 = Filik | first5 = L. | last6 = Astarci | first6 = MH. | last7 = Ustün | first7 = H. | last8 = Ustündağ | first8 = Y. | last9 = Akbal | first9 = E. | title = Do scattered white spots in the duodenum mark a specific gastrointestinal pathology? | journal = J Dig Dis | volume = 10 | issue = 4 | pages = 300-4 | month = Nov | year = 2009 | doi = 10.1111/j.1751-2980.2009.00399.x | PMID = 19906109 | URL = http://onlinelibrary.wiley.com/doi/10.1111/j.1751-2980.2009.00399.x/pdf }}</ref>
 
===Microscopic===
Features:
*+/-Loss of villi.
*Intraepithelial lymphocytes.
**+Other inflammatory cells, especially PMNs, close to the luminal surface.
*Flagellate protozoa -- '''diagnostic feature'''.
**Organisms often at site of bad inflammation.
**Pale/translucent on H&E.
**Size: 12-15 micrometers (long axis) x 6-10 micrometers (short axis) -- if seen completely.<ref>[http://www.water-research.net/Giardia.htm http://www.water-research.net/Giardia.htm]</ref>
***Often look like a crescent moon ([http://en.wikipedia.org/wiki/File:Crescent_Moon.JPG image of crescent moon]) or semicircular<ref>[http://en.wikipedia.org/wiki/Semicircle http://en.wikipedia.org/wiki/Semicircle]</ref> -- as the long axis of the organism is rarely in the plane of the (histologic) section.
 
Note:
*Changes are typically diffuse, i.e. if multiple biopsies are done the changes are present in all fragments.<ref name=pmid18354756>{{Cite journal  | last1 = Freeman | first1 = HJ. | title = Pearls and pitfalls in the diagnosis of adult celiac disease. | journal = Can J Gastroenterol | volume = 22 | issue = 3 | pages = 273-80 | month = Mar | year = 2008 | doi =  | PMID = 18354756 }}</ref>
 
DDx:
*[[Celiac disease]] - near perfect mimic; missing giardia organisms.
 
====Images====
<gallery>
Image:Giardiasis_duodenum_high.jpg | Giardiasis - high mag. (WC)
Image:Giardiasis_duodenum_low.jpg | Giardiasis - low mag. (WC)
</gallery>
www:
*[http://path.upmc.edu/cases/case278.html Giardiasis - several crappy images (upmc.edu)].
 
===Stains===
*Methylene blue +ve.<ref name=pmid23285438>{{Cite journal  | last1 = Rajurkar | first1 = MN. | last2 = Lall | first2 = N. | last3 = Basak | first3 = S. | last4 = Mallick | first4 = SK. | title = A simple method for demonstrating the giardia lamblia trophozoite. | journal = J Clin Diagn Res | volume = 6 | issue = 9 | pages = 1492-4 | month = Nov | year = 2012 | doi = 10.7860/JCDR/2012/4358.2541 | PMID = 23285438 }}</ref>
 
===IHC===
*CD117 +ve.<ref name=pmid18835628>{{Cite journal  | last1 = Sinelnikov | first1 = I. | last2 = Sion-Vardy | first2 = N. | last3 = Shaco-Levy | first3 = R. | title = C-kit (CD117) immunostain is useful for the diagnosis of Giardia lamblia in duodenal biopsies. | journal = Hum Pathol | volume = 40 | issue = 3 | pages = 323-5 | month = Mar | year = 2009 | doi = 10.1016/j.humpath.2008.07.015 | PMID = 18835628 }}</ref>
 
===Sign out===
<pre>
DUODENUM, BIOPSY:
- SMALL BOWEL MUCOSA WITH BRUNNER'S GLANDS AND MICROORGANISMS CONSISTENT WITH GIARDIA.
</pre>


==Acute duodenitis==
==Acute duodenitis==
*Abbreviated ''AD''.
*Abbreviated ''AD''.
===General===
{{Main|Acute duodenitis}}
DDx:
*Infection.
**Helicobactor organisms in the [[stomach]].
*Medications ([[NSAID]]s).
*[[Crohn's disease]] (usually focal/patchy).
*[[Portal hypertension]] (portal hypertensive duodenopathy).<ref name=pmid12003421>{{Cite journal  | last1 = Shudo | first1 = R. | last2 = Yazaki | first2 = Y. | last3 = Sakurai | first3 = S. | last4 = Uenishi | first4 = H. | last5 = Yamada | first5 = H. | last6 = Sugawara | first6 = K. | title = Duodenal erosions, a common and distinctive feature of portal hypertensive duodenopathy. | journal = Am J Gastroenterol | volume = 97 | issue = 4 | pages = 867-73 | month = Apr | year = 2002 | doi = 10.1111/j.1572-0241.2002.05602.x | PMID = 12003421 }}</ref>
*[[Celiac sprue]].
 
===Microscopic===
Features:
*Intraepithelial lymphocytes.
*Neutrophils - "found without searching" - '''key feature'''.
*Eosinophils - "found without searching" - '''key feature'''.
*Plasma cells (increased).
 
Notes:
*One needs stomach concurrent biopsies to r/o Helicobactor.
*Erosions make celiac sprue much less likely.
*Presence of chronic inflammation useful for NSAIDs vs. Helicobacter organisms:
**[[NSAID]]s not commonly assoc. with acute inflammation;<ref name=pmid8406146>{{cite journal |author=Taha AS, Dahill S, Nakshabendi I, Lee FD, Sturrock RD, Russell RI |title=Duodenal histology, ulceration, and Helicobacter pylori in the presence or absence of non-steroidal anti-inflammatory drugs |journal=Gut |volume=34 |issue=9 |pages=1162–6 |year=1993 |month=September |pmid=8406146 |pmc=1375446 |doi= |url=}}</ref> thus, without chronic inflammation NSAIDs are unlikely.
***Acute NSAID-related duodenitis reported.<ref name=pmid18158085>{{cite journal |author=Hashash JG, Atweh LA, Saliba T, ''et al.'' |title=Acute NSAID-related transmural duodenitis and extensive duodenal ulceration |journal=Clin Ther |volume=29 |issue=11 |pages=2448–52 |year=2007 |month=November |pmid=18158085 |doi=10.1016/j.clinthera.2007.11.012 |url=}}</ref>
 
===Sign out===
<pre>
DUODENUM, BIOPSY:
- ACUTE DUODENITIS.
</pre>
 
====Acute on chronic duodenitis====
<pre>
DUODENUM, BIOPSY:
- ACUTE ON CHRONIC DUODENITIS.
</pre>
 
=====Micro=====
The sections show small bowel mucosa with intraepithelial neutrophils. The epithelium shows nuclear hyperchromasia, pseudostratification and nuclear enlargement; however, it matures toward the surface (reactive changes of the epithelium).
 
Brunner's glands are found focally in the lamina propria. Gastric foveolar-type epithelium
is identified. Lamina propria plasma cells are abundant.


==Chronic duodenitis==
==Chronic duodenitis==
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==Peptic duodenitis==
==Peptic duodenitis==
===General===
{{Main|Peptic duodenitis}}
*A somewhat controversial type of [[chronic duodenitis]].
*Considered to be a consequence of [[peptic ulcer disease]] ([[Helicobacter gastritis]]).
*One of the key components of the diagnosis is foveolar metaplasia and it is disputed that this is really due to Helicobacter.
**Genta ''et al.'' consider gastric foveolar metaplasia a congenital lesion.<ref name=pmid20656325>{{Cite journal  | last1 = Genta | first1 = RM. | last2 = Kinsey | first2 = RS. | last3 = Singhal | first3 = A. | last4 = Suterwala | first4 = S. | title = Gastric foveolar metaplasia and gastric heterotopia in the duodenum: no evidence of an etiologic role for Helicobacter pylori. | journal = Hum Pathol | volume = 41 | issue = 11 | pages = 1593-600 | month = Nov | year = 2010 | doi = 10.1016/j.humpath.2010.04.010 | PMID = 20656325 }}</ref>
 
===Microscopic===
Features:<ref name=Ref_GLP145>{{Ref GLP|145}}</ref>
*Gastric foveolar metaplasia - '''key feature'''.
*[[Brunner's gland hyperplasia]].
*+/-Inflammation - neutrophils.{{fact}}
*Ulceration.{{fact}}
 
DDx:
*[[Chronic duodenitis]] not otherwise specified - no foveolar metaplasia, abundant plasma cells.
*[[Acute duodenitis]].
*[[Brunner's gland hyperplasia]].
 
====Images====
<gallery>
Image:Duodenum_with_foveolar_metaplasia_-_low_mag.jpg | Duodenum with foveolar metaplasia - low mag. (WC/Nephron)
Image:Duodenum_with_foveolar_metaplasia_-_intermed_mag.jpg | Duodenum with foveolar metaplasia - intermed. mag. (WC/Nephron)
Image:Duodenum_with_foveolar_metaplasia_-_alt_-_very_high_mag.jpg | Duodenum with foveolar metaplasia - very high mag. (WC/Nephron)
</gallery>
===Stains===
Foveolar metaplasia:
*[[PAS stain]] +ve.<ref name=Ref_GLP145>{{Ref GLP|145}}</ref>
*[[Mucicarmine stain]] +ve.
 
===Sign out===
====Foveolar metaplasia only====
<pre>
DUODENUM, BIOPSY:
- SMALL BOWEL MUCOSA WITH FOCAL GASTRIC FOVEOLAR METAPLASIA.
- BRUNNER'S GLANDS NOT IDENTIFIED.
- VILLI AND INTRAEPITHELIAL LYMPHOCYTES WITHIN NORMAL LIMITS (NEGATIVE FOR CELIAC DISEASE).
- NEGATIVE FOR ACUTE DUODENITIS.
</pre>
 
====Chronic duodenitis====
<pre>
DUODENUM, BIOPSY:
- SMALL BOWEL MUCOSA WITH BRUNNER'S GLAND IN THE LAMINA PROPRIA AND
  GASTRIC FOVEOLAR METAPLASIA -- CONSISTENT WITH CHRONIC DUODENITIS.
- NEGATIVE FOR ACUTE DUODENITIS.
- NEGATIVE FOR MALIGNANCY.
</pre>
 
=====Micro=====
The sections show small bowel mucosa and a small amount of submucosa. Brunner's glands are abundant and found focally in the lamina propria. Gastric foveolar-type epithelium is identified. Intraepithelial neutrophils are not identified.
 
The epithelium matures appropriately. There is no increase in intraepithelial lymphocytes.


==Brunner's gland hyperplasia==
==Brunner's gland hyperplasia==
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DDx:
DDx:
*Foveolar metaplasia (isolated) - see [[peptic duodenitis]].
*[[Peptic duodenitis]].
*[[Peptic duodenitis]].


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- SMALL BOWEL MUCOSA WITHOUT SIGNIFICANT PATHOLOGY.
- SMALL BOWEL MUCOSA WITHOUT SIGNIFICANT PATHOLOGY.
- PROMINENT BRUNNER'S GLANDS WITH EXTENSION INTO THE LAMINA PROPRIA.
- PROMINENT BRUNNER'S GLANDS WITH EXTENSION INTO THE LAMINA PROPRIA.
</pre>
====Superficial Brunner's glands====
<pre>
DUODENUM, BIOPSY:
- SMALL BOWEL MUCOSA WITH BRUNNER'S GLANDS THAT ARE FOCALLY SUPERFICIAL.
- NO FINDINGS SUGGESTIVE OF CELIAC DISEASE.
- NEGATIVE FOR ACTIVE INFLAMMATION.
- NEGATIVE FOR DYSPLASIA.
</pre>
</pre>


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==Whipple disease==
==Whipple disease==
===General===
{{Main|Whipple's disease}}
Etiology:
*Infection - caused by ''Tropheryma whipplei''<ref name=pmid11777846>{{cite journal |author=Liang Z, La Scola B, Raoult D |title=Monoclonal antibodies to immunodominant epitope of Tropheryma whipplei |journal=Clin. Diagn. Lab. Immunol. |volume=9 |issue=1 |pages=156?9 |year=2002 |month=January |pmid=11777846 |pmc=119894 |doi= |url=http://cvi.asm.org/cgi/pmidlookup?view=long&pmid=11777846}}</ref> a rod-shaped organisms.<ref name=pmid11764080>{{Cite journal  | last1 = Alkan | first1 = S. | last2 = Beals | first2 = TF. | last3 = Schnitzer | first3 = B. | title = Primary diagnosis of whipple disease manifesting as lymphadenopathy: use of polymerase chain reaction for detection of Tropheryma whippelii. | journal = Am J Clin Pathol | volume = 116 | issue = 6 | pages = 898-904 | month = Dec | year = 2001 | doi = 10.1309/7678-E2DW-HFJ5-QYUJ | PMID = 11764080 }}</ref>
 
Epidemiology:
*Very rare.
*Classically middle aged men.
 
====Clinical====
*Malabsorption (diarrhea), arthritis + others.
**Symptoms are non-specific.
 
Treatment:
*Antibiotics - for months and months.
 
===Microscopic===
Features:<ref name=pmid15476147>{{cite journal | author=Bai J, Mazure R, Vazquez H, Niveloni S, Smecuol E, Pedreira S, Mauriño E | title=Whipple's disease | journal=Clin Gastroenterol Hepatol | volume=2 | issue=10 | pages=849?60 | year=2004 | pmid=15476147  | doi=10.1016/S1542-3565(04)00387-8}}</ref>
*Infectious microorganism typically found in macrophages.
**Macrophages usually abundant - '''key feature''' that should raise Dx in DDx.
**Organisms periodic acid-Schiff (PAS) positive.
 
DDx:
*[[Mycobacterium avium complex]] (MAC).
 
====Images====
<gallery>
Image:Whipple_disease_-_intermed_mag.jpg | Whipple disease - intermed. mag. (WC)
Image:Whipple_disease_-a-_high_mag.jpg | Whipple disease - high mag. (WC)
Image:Whipple2.jpg | Whipple disease - poor quality - low mag. (WC)
</gallery>
===Stains===
*PAS +ve organisms.
*AFB stain -ve -- to r/o MAI.
 
Image:
*[http://www.biomedcentral.com/content/figures/1472-6823-6-3-2-l.jpg Whipple disease - PAS stain (biomedcentral.com)].


==Microvillous inclusion disease==
==Microvillous inclusion disease==
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==Gangliocytic paraganglioma==
==Gangliocytic paraganglioma==
*Abbreviated ''GP''.
*Abbreviated ''GP''.
===General===
{{Main|Gangliocytic paraganglioma}}
*Extremely rare.<ref name=pmid22340577>{{Cite journal  | last1 = Wu | first1 = GC. | last2 = Wang | first2 = KL. | last3 = Zhang | first3 = ZT. | title = Gangliocytic paraganglioma of the duodenum: a case report. | journal = Chin Med J (Engl) | volume = 125 | issue = 2 | pages = 388-9 | month = Jan | year = 2012 | doi =  | PMID = 22340577 }}</ref>
*May be associated with [[neurofibromatosis type 1]].<ref name=pmid12754392>{{Cite journal  | last1 = Castoldi | first1 = L. | last2 = De Rai | first2 = P. | last3 = Marini | first3 = A. | last4 = Ferrero | first4 = S. | last5 = De Luca | first5 = V. | last6 = Tiberio | first6 = G. | title = Neurofibromatosis-1 and Ampullary Gangliocytic Paraganglioma Causing Biliary and Pancreatic Obstruction. | journal = Int J Gastrointest Cancer | volume = 29 | issue = 2 | pages = 93-98 | month =  | year = 2001 | doi =  | PMID = 12754392 }}</ref>
*Classified a [[neuroendocrine tumour]].<ref>URL: [http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/SmallbowelNET_11protocol.pdf http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/SmallbowelNET_11protocol.pdf]. Accessed on: 29 March 2012.</ref>
*Usually has a mix of the features seen in: [[neuroendocrine tumour]]s, [[paraganglioma]]s and [[ganglioneuroma]]s.
 
Clinical - presentation:<ref name=pmid21599949/>
*GI bleed ~ 45% of cases.
*Abdominal pain ~ 43% of cases.
*[[Anemia]] ~ 15% of cases.
 
===Gross===
*Classically in the duodenum ~90% of cases.<ref name=pmid21599949>{{Cite journal  | last1 = Okubo | first1 = Y. | last2 = Wakayama | first2 = M. | last3 = Nemoto | first3 = T. | last4 = Kitahara | first4 = K. | last5 = Nakayama | first5 = H. | last6 = Shibuya | first6 = K. | last7 = Yokose | first7 = T. | last8 = Yamada | first8 = M. | last9 = Shimodaira | first9 = K. | title = Literature survey on epidemiology and pathology of gangliocytic paraganglioma. | journal = BMC Cancer | volume = 11 | issue =  | pages = 187 | month =  | year = 2011 | doi = 10.1186/1471-2407-11-187 | PMID = 21599949 }}</ref>
 
===Microscopic===
Features - three components:<ref name=pmid15740625>{{Cite journal  | last1 = Wong | first1 = A. | last2 = Miller | first2 = AR. | last3 = Metter | first3 = J. | last4 = Thomas | first4 = CR. | title = Locally advanced duodenal gangliocytic paraganglioma treated with adjuvant radiation therapy: case report and review of the literature. | journal = World J Surg Oncol | volume = 3 | issue = 1 | pages = 15 | month = Mar | year = 2005 | doi = 10.1186/1477-7819-3-15 | PMID = 15740625 }}</ref><ref>URL: [http://surgpathcriteria.stanford.edu/gitumors/gangliocytic-paraganglioma/printable.html http://surgpathcriteria.stanford.edu/gitumors/gangliocytic-paraganglioma/printable.html]. Accessed on: 31 May 2012.</ref>
#Ganglion cells = large cells with:
#*Round large nucleus.
#*Prominent [[nucleolus]].
#*Moderate or abundant cytoplasm.
#Epithelioid cells (neuroendocrine component):
#*Arranged in nests or cords.
#*Stippled chromatin.
#Spindle cells ([[Schwannoma|schwannian]] component):
#*Moderate or abundant cytoplasm.
#*Nucleus spindle-shaped or ellipsoid.
 
DDx:<ref name=pmid15740625/>
*Poorly differentiated carcinoma.
*[[Neuroendocrine tumour]].
*[[Paraganglioma]].
 
Images:
*[[WC]]:
**[http://commons.wikimedia.org/wiki/File:Gangliocytic_paraganglioma_-_intermed_mag.jpg GP - intermed. mag. (WC)].
**[http://commons.wikimedia.org/wiki/File:Gangliocytic_paraganglioma_-_very_high_mag.jpg GP - very high mag. (WC)].
**[http://commons.wikimedia.org/wiki/File:Gangliocytic_paraganglioma_-_2_-_intermed_mag.jpg GP - 2 - intermed. mag. (WC)].
*www:
**[http://www.wjso.com/content/3/1/15/figure/F2 Epithelioid cells of a GP (wjso.com)].
**[http://www.wjso.com/content/3/1/15/figure/F4 Ganglion cell in a GP (wjso.com)].
**[http://www.pubcan.org/images/large/Fig_5-17_A.jpg Ganglion cells in a GP (pubcan.org)].<ref>URL: [http://www.pubcan.org/printicdotopo.php?id=5028 http://www.pubcan.org/printicdotopo.php?id=5028]. Accessed on: 15 April 2012.</ref>
**[http://www.surgicalpathologyatlas.com/glfusion/mediagallery/media.php?f=0&sort=0&s=20080802175012135 GP (surgicalpathologyatlas.com)].
 
===IHC===
*Synaptophysin +ve.
*CD56 +ve.
*Chromogranin A +ve.
*HU +ve in ganglion-like cells.
*S100 +ve in spindle cells & sustentacular cells.


==Pseudomelanosis duodeni==
==Pseudomelanosis duodeni==
===General===
{{Main|Pseudomelanosis duodeni}}
*Rare.
*Consists of iron and lipofuscin.<ref name=pmid2458404>{{Cite journal  | last1 = Lin | first1 = HJ. | last2 = Tsay | first2 = SH. | last3 = Chiang | first3 = H. | last4 = Tsai | first4 = YT. | last5 = Lee | first5 = SD. | last6 = Yeh | first6 = YS. | last7 = Lo | first7 = GH. | title = Pseudomelanosis duodeni. Case report and review of literature. | journal = J Clin Gastroenterol | volume = 10 | issue = 2 | pages = 155-9 | month = Apr | year = 1988 | doi =  | PMID = 2458404 }}
</ref>
 
Associations:<ref name=pmid18253910/>
*[[Hypertension]] ~90% of cases.
*Iron supplementation ~75% of cases.
*End-stage renal disease ~60% of cases.
 
Note:
*The associations are different than for ''[[melanosis coli]]''.
 
===Gross/endoscopic===
*Dark spots ~35% of cases.<ref name=pmid18253910>{{Cite journal  | last1 = Giusto | first1 = D. | last2 = Jakate | first2 = S. | title = Pseudomelanosis duodeni: associated with multiple clinical conditions and unpredictable iron stainability - a case series. | journal = Endoscopy | volume = 40 | issue = 2 | pages = 165-7 | month = Feb | year = 2008 | doi = 10.1055/s-2007-995472 | PMID = 18253910 }}</ref>
 
===Microscopic===
Features:
*Dark pigment in the lamina propria macrophages.
 
Images:
*[http://path.upmc.edu/cases/case616.html Pseudomelanosis duodeni - several images (upmc.edu)].
 
===Stains===
*Prussian blue +ve ~80% of cases.<ref name=pmid18253910/>


=Tumours=
=Tumours=
Line 540: Line 266:
*[[AKA]] ''duodenal adenocarcinoma''.
*[[AKA]] ''duodenal adenocarcinoma''.
*[[AKA]] ''duodenal carcinoma''.
*[[AKA]] ''duodenal carcinoma''.
 
{{Main|Adenocarcinoma of the duodenum}}
===General===
*Duodenum - most common site in small bowel.
**[[Ampulla of Vater]] most common site in the duodenum - see ''[[ampullary carcinoma]]''.
 
Risk factors:
*[[Crohn's disease]].
*[[Celiac sprue]].
*[[Familial adenomatous polyposis]] (FAP).
*[[HNPCC]].
*[[Peutz-Jeghers syndrome]].
 
===Gross===
*Mass ulcerating or exophytic.
 
Image:
<gallery>
Image:Duodenal adenocarcinoma.png | Duodenal adenocarcinoma - endoscopy. (WC/Samir)
</gallery>
 
===Microscopic===
Features:
*Similar to large bowel adenocarcinomas - see ''[[colorectal tumours]]'' article.
 
DDx:
*[[Ampullary carcinoma]].
 
===IHC===
*SMAD4 -ve/+ve.<ref name=pmid15157044>{{Cite journal  | last1 = Bläker | first1 = H. | last2 = Aulmann | first2 = S. | last3 = Helmchen | first3 = B. | last4 = Otto | first4 = HF. | last5 = Rieker | first5 = RJ. | last6 = Penzel | first6 = R. | title = Loss of SMAD4 function in small intestinal adenocarcinomas: comparison of genetic and immunohistochemical findings. | journal = Pathol Res Pract | volume = 200 | issue = 1 | pages = 1-7 | month =  | year = 2004 | doi =  | PMID = 15157044 }}</ref>


==Duodenal neuroendocrine tumour==
==Duodenal neuroendocrine tumour==
{{Main|Neuroendocrine tumours}}
{{Main|Neuroendocrine tumours}}
:''Duodenal NET'' redirects here.
===General===
===General===
*Like [[neuroendocrine tumours]] elsewhere.
*Like [[neuroendocrine tumours]] elsewhere.
Line 600: Line 299:
Image:Small_intestine_neuroendocrine_tumour_high_mag.jpg | Neuroendocrine tumour - high mag. (WC)
Image:Small_intestine_neuroendocrine_tumour_high_mag.jpg | Neuroendocrine tumour - high mag. (WC)
</gallery>
</gallery>
===Sign out===
<pre>
Duodenum, Biopsy:
- Incidental neuroendocrine tumour, grade 1, see comment.
- Background small bowel mucosa with Brunner's glands within normal limits.
Comment:
The tumour stains as follows:
POSITIVE: AE1/AE3, CD56, synaptophysin.
NEGATIVE: S-100, CD68.
PROLIFERATION (Ki-67): <2%.
</pre>


==Ampullary tumours==
==Ampullary tumours==
Line 616: Line 328:
===Sign out===
===Sign out===
*Ampullary carcinoma - has separate staging.
*Ampullary carcinoma - has separate staging.
==Traditional adenoma==
:''Duodenal adenoma'' redirects here.
{{Main|Traditional adenoma}}
===General===
*Strong association of [[familial adenomatous polyposis]].
**In one series of 208 adenomas, almost 70% were from FAP patients.<ref name=pmid16837629/>
*Commonly found in association foveolar metaplasia - especially in sporadic cases ~60% of cases.
**In FAP ~30% of cases have foveolar metaplasia.<ref name=pmid16837629>{{Cite journal  | last1 = Rubio | first1 = CA. | title = Gastric duodenal metaplasia in duodenal adenomas. | journal = J Clin Pathol | volume = 60 | issue = 6 | pages = 661-3 | month = Jun | year = 2007 | doi = 10.1136/jcp.2006.039388 | PMID = 16837629 | PMC = 1955048}}</ref>
*A colonscopy is recommended in individuals with nonampullary duodenal adenomas, as they are likely at increased risk of large bowel adenomas.<ref name=pmid26811631>{{Cite journal  | last1 = Lim | first1 = CH. | last2 = Cho | first2 = YS. | title = Nonampullary duodenal adenoma: Current understanding of its diagnosis, pathogenesis, and clinical management. | journal = World J Gastroenterol | volume = 22 | issue = 2 | pages = 853-61 | month = Jan | year = 2016 | doi = 10.3748/wjg.v22.i2.853 | PMID = 26811631 }}</ref>
===Sign out===
<pre>
POLYP, DUODENUM, EXCISION:
- TUBULAR ADENOMA.
-- NEGATIVE FOR HIGH-GRADE DYSPLASIA.
</pre>
====Alternate====
<pre>
Polyp (Nonampullary), Duodenum, Polypectomy:
    - Tubular adenoma, NEGATIVE for high-grade dysplasia.
Comment:
A colonscopy is recommended if not done recently, as individual with nonampullary duodenal adenomas are likely at increased risk of large bowel adenomas.[1]
1. Therap Adv Gastroenterol. 2012 Mar; 5(2): 127138. doi: 10.1177/1756283X11429590
</pre>


=See also=
=See also=

Revision as of 22:27, 14 February 2019

Schematic of the duodenum. (WC/Luke Guthmann)

The duodenum is the first part of the small bowel and receives food from the stomach. It is accessible by EGD (esophagogastroduodenoscopy) and frequently biopsied.

An introduction to gastrointestinal pathology is in the gastrointestinal pathology article.

The clinical history is often: r/o celiac or r/o giardia.

Getting started

Normal duodenum

  • Abbreviated ND.

General

  • Very common.

Microscopic

  • Three tall villi.
  • Few intraepithelial lymphocytes; < 1 lymphocyte / 4 epithelial cells.
  • No (pink) subepithelial collagen band.
  • Predominant lamina propria cell: plasma cells.
  • No organisms in lumen.

DDx:

Sign out

Duodenum, Biopsy:
- Small bowel mucosa and Brunner's glands within normal limits.
Duodenum, Biopsy:
- Small bowel mucosa within normal limits.
Duodenum, Biopsy:
- Small bowel mucosa within normal limits.
- NEGATIVE for findings suggestive of celiac disease.
Small Bowel (Duodenum), Biopsy:
- Small bowel mucosa within normal limits.
- NEGATIVE for findings suggestive of celiac disease.

Block letters

DUODENUM, BIOPSY: 
- SMALL BOWEL MUCOSA AND BRUNNER'S GLANDS WITHIN NORMAL LIMITS.
DUODENUM, BIOPSY: 
- SMALL BOWEL MUCOSA WITHIN NORMAL LIMITS.
DUODENUM, BIOPSY: 
- SMALL BOWEL MUCOSA WITHIN NORMAL LIMITS.
- NEGATIVE FOR FINDINGS SUGGESTIVE OF CELIAC DISEASE.
SMALL BOWEL (DUODENUM), BIOPSY: 
- SMALL BOWEL MUCOSA WITHIN NORMAL LIMITS.
- NEGATIVE FOR FINDINGS SUGGESTIVE OF CELIAC DISEASE.

Basic DDx

  • Celiac sprue.
    • Intraepithelial lymphocytes - key feature.
    • Loss of villi.
  • Giardia.
    • Like celiac... but giardia organisms.
  • Adenomas.
    • Too much blue - similar to colonic adenomas.
  • Cancer.
    • Too much blue and epithelium in the wrong place.

More

  • H. pylori only in areas of gastric metaplasia.[2]

Duodenal nodules DDX

 
 
 
 
 
 
 
 
 
 
 
 
Duodenal
nodule
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Benign
(common)
 
 
 
 
 
 
 
 
 
 
 
 
 
Neoplastic
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Brunner's
gland
 
Heterotopic
gastric mucosa
 
Lymphoid
nodule
 
Adenoma
 
NET
 
Paraganglioma
 
Prolapsed
gastric polyp
 
Metastasis
 
 
 
 

Infections of the duodenum[3]

Common:

Rare:

Common stuffs

Gastric heterotopia of the duodenum

  • AKA heterotopic gastric mucosa.

Celiac sprue

  • AKA celiac disease.

Giardiasis

Acute duodenitis

  • Abbreviated AD.

Chronic duodenitis

General

  • This is not very well defined as plasma cells are present in a normal duodenum.

Gross

  • Duodenal erythema.

Microscopic

Features:

DDx:

Sign out

DUODENUM, BIOPSY:
- MODERATE NON-SPECIFIC CHRONIC DUODENTIS (SMALL BOWEL MUCOSA WITH VILLOUS
  BLUNTING, PROMINENT BRUNNER'S GLANDS, ABUNDANT LAMINA PROPRIA PLASMA CELLS
  AND OCCASIONAL INTRAEPITHELIAL LYMPHOCYTES, WITHOUT FOVEOLAR METAPLASIA).
- NEGATIVE FOR DYSPLASIA.

Peptic duodenitis

Brunner's gland hyperplasia

Brunner's gland hamartoma redirects here.
  • Abbreviated BGH.
  • AKA Brunneroma.[4]

General

  • Benign.
  • Usually asymptomatic.[5]

Note:

  • The AFIP uses the term Brunner's gland hamartoma for lesions > 5 mm.[6]
    • Multiple lesions less than 5 mm are hyperplasia.

Gross

  • Nodularity of the duodenum.

Microscopic

Features:

  • Prominent Brunner's gland.
    • Tubular structures - formed by cells abundant cytoplasm that is clear with eosinophilic "cobwebs" and a round, small basal nucleus without a nucleolus.
    • Brunner's glands close to the surface epithelium - key feature.[7]
  • +/-Pancreatic acini and ducts.[6]

DDx:

Image:

Sign out

DUODENUM, BIOPSY:
- CONSISTENT WITH BRUNNER'S GLAND HYPERPLASIA.
- SMALL BOWEL MUCOSA WITHOUT SIGNIFICANT PATHOLOGY.
 DUODENUM, BIOPSY:
- SMALL BOWEL MUCOSA WITHOUT SIGNIFICANT PATHOLOGY.
- PROMINENT BRUNNER'S GLANDS WITH EXTENSION INTO THE LAMINA PROPRIA.

Superficial Brunner's glands

DUODENUM, BIOPSY:
- SMALL BOWEL MUCOSA WITH BRUNNER'S GLANDS THAT ARE FOCALLY SUPERFICIAL.
- NO FINDINGS SUGGESTIVE OF CELIAC DISEASE.
- NEGATIVE FOR ACTIVE INFLAMMATION.
- NEGATIVE FOR DYSPLASIA.

Micro

The sections show small bowel mucosa and a small amount of submucosa. Brunner's glands are abundant and found focally in the lamina propria.

The epithelium matures appropriately. There is no increase in intraepithelial lymphocytes. No foveolar metaplasia of the epithelium is identified.

Weird stuff

Disaccharidases deficiency

General

  • Common among asians.
  • Includes: lactase, sucrase, and maltase.
    • Lactase changes seen with mild histomorphologic changes.[8]
    • Maltase and sucrase only affected in moderate and severe lesions.

Microscopic

Features:[8]

  • Decreased villous-crypt ratio (mild to severe).
  • +/-Inflammation (only in moderate and severe).

DDx:

  • Celiac disease.[9]

Notes:

  • May have normal histomorphology.[8]

Whipple disease

Microvillous inclusion disease

This rare disease presents very shortly after birth.

Tufting enteropathy

  • AKA intestinal epithelial dysplasia.

General

  • Genetic disease[10] - related to abnormal enterocytes (development and/or differentiation).
    • Gene implicated: EPCAM.[11]

Microscopic

Features:[12]

  • Villous atrophy
  • Mononuclear cell infiltration of the lamina propria
  • Abnormal surface enterocytes:
    • Focal crowding -- resembling tufts.


Gangliocytic paraganglioma

  • Abbreviated GP.

Pseudomelanosis duodeni

Tumours

Lymphoma

Note:

Adenocarcinoma of the duodenum

  • AKA duodenal adenocarcinoma.
  • AKA duodenal carcinoma.

Duodenal neuroendocrine tumour

Duodenal NET redirects here.

General

Associations:

Microscopic

Features:[16]

  • Usu. nests of cells - may be:
    • Trabecular.
    • Glandular - common in stomatostatin producing tumours.
  • Stippled chromatin - (AKA salt-and-pepper chromatin, coarse chromatin).
  • Classically subepithelial/mural.
  • +/-Psammoma bodies - suggestive of somatostatinoma and NF1.[17]

DDx:

Images

Sign out

Duodenum, Biopsy:
	- Incidental neuroendocrine tumour, grade 1, see comment.
	- Background small bowel mucosa with Brunner's glands within normal limits.

Comment:
The tumour stains as follows:
POSITIVE: AE1/AE3, CD56, synaptophysin.
NEGATIVE: S-100, CD68.
PROLIFERATION (Ki-67): <2%.

Ampullary tumours

General

  • Individuals with high-grade dysplasia (on biopsy) are usually treated with a pancreaticoduodenectomy (Whipple procedure), as local resections have a very high recurrence rate.[18]

Microscopic

Features:

DDx:

Sign out

  • Ampullary carcinoma - has separate staging.

Traditional adenoma

Duodenal adenoma redirects here.

General

  • Strong association of familial adenomatous polyposis.
    • In one series of 208 adenomas, almost 70% were from FAP patients.[19]
  • Commonly found in association foveolar metaplasia - especially in sporadic cases ~60% of cases.
    • In FAP ~30% of cases have foveolar metaplasia.[19]
  • A colonscopy is recommended in individuals with nonampullary duodenal adenomas, as they are likely at increased risk of large bowel adenomas.[20]

Sign out

POLYP, DUODENUM, EXCISION:
- TUBULAR ADENOMA.
-- NEGATIVE FOR HIGH-GRADE DYSPLASIA.

Alternate

Polyp (Nonampullary), Duodenum, Polypectomy:
     - Tubular adenoma, NEGATIVE for high-grade dysplasia.

Comment:
A colonscopy is recommended if not done recently, as individual with nonampullary duodenal adenomas are likely at increased risk of large bowel adenomas.[1]

1. Therap Adv Gastroenterol. 2012 Mar; 5(2): 127138. doi: 10.1177/1756283X11429590

See also

References

  1. Agarwal S, Smereka P, Harpaz N, Cunningham-Rundles C, Mayer L (July 2010). "Characterization of immunologic defects in patients with common variable immunodeficiency (CVID) with intestinal disease". Inflamm Bowel Dis. doi:10.1002/ibd.21376. PMID 20629103.
  2. El-Zimaity. 18 October 2010.
  3. Serra S, Jani PA (November 2006). "An approach to duodenal biopsies". J. Clin. Pathol. 59 (11): 1133–50. doi:10.1136/jcp.2005.031260. PMC 1860495. PMID 16679353. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1860495/?tool=pubmed.
  4. Tan, YM.; Wong, WK. (2002). "Giant Brunneroma as an unusual cause of upper gastrointestinal hemorrhage: report of a case.". Surg Today 32 (10): 910-2. doi:10.1007/s005950200179. PMID 12376792.
  5. 5.0 5.1 Lee, WC.; Yang, HW.; Lee, YJ.; Jung, SH.; Choi, GY.; Go, H.; Kim, A.; Cha, SW. (Jun 2008). "Brunner's gland hyperplasia: treatment of severe diffuse nodular hyperplasia mimicking a malignancy on pancreatic-duodenal area.". J Korean Med Sci 23 (3): 540-3. doi:10.3346/jkms.2008.23.3.540. PMID 18583897.
  6. 6.0 6.1 6.2 Patel, ND.; Levy, AD.; Mehrotra, AK.; Sobin, LH. (Sep 2006). "Brunner's gland hyperplasia and hamartoma: imaging features with clinicopathologic correlation.". AJR Am J Roentgenol 187 (3): 715-22. doi:10.2214/AJR.05.0564. PMID 16928936.
  7. Franzin, G.; Musola, R.; Ghidini, O.; Manfrini, C.; Fratton, A. (Dec 1985). "Nodular hyperplasia of Brunner's glands.". Gastrointest Endosc 31 (6): 374-8. PMID 4076734.
  8. 8.0 8.1 8.2 Langman JM, Rowland R (July 1990). "Activity of duodenal disaccharidases in relation to normal and abnormal mucosal morphology". J. Clin. Pathol. 43 (7): 537–40. PMC 502575. PMID 2116456. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC502575/.
  9. Murray IA, Smith JA, Coupland K, Ansell ID, Long RG (February 2001). "Intestinal disaccharidase deficiency without villous atrophy may represent early celiac disease". Scand. J. Gastroenterol. 36 (2): 163–8. PMID 11252408.
  10. Online 'Mendelian Inheritance in Man' (OMIM) 613217
  11. Online 'Mendelian Inheritance in Man' (OMIM) 185535
  12. Goulet O, Salomon J, Ruemmele F, de Serres NP, Brousse N (2007). "Intestinal epithelial dysplasia (tufting enteropathy)". Orphanet J Rare Dis 2: 20. doi:10.1186/1750-1172-2-20. PMC 1878471. PMID 17448233. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1878471/.
  13. Chetty, R. (Apr 2008). "Requiem for the term 'carcinoid tumour' in the gastrointestinal tract?". Can J Gastroenterol 22 (4): 357-8. PMID 18414708.
  14. Klöppel, G.; Perren, A.; Heitz, PU. (Apr 2004). "The gastroenteropancreatic neuroendocrine cell system and its tumors: the WHO classification.". Ann N Y Acad Sci 1014: 13-27. PMID 15153416.
  15. Klöppel G (July 2003). "[Neuroendocrine tumors of the gastrointestinal tract]" (in German). Pathologe 24 (4): 287–96. doi:10.1007/s00292-003-0636-7. PMID 14513276.
  16. URL: http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/SmallbowelNET_11protocol.pdf. Accessed on: 29 March 2012.
  17. Kim, JA.; Choi, WH.; Kim, CN.; Moon, YS.; Chang, SH.; Lee, HR. (Mar 2011). "Duodenal somatostatinoma: a case report and review.". Korean J Intern Med 26 (1): 103-7. doi:10.3904/kjim.2011.26.1.103. PMID 21437171.
  18. Meneghetti, AT.; Safadi, B.; Stewart, L.; Way, LW. (Dec 2005). "Local resection of ampullary tumors.". J Gastrointest Surg 9 (9): 1300-6. doi:10.1016/j.gassur.2005.08.031. PMID 16332486.
  19. 19.0 19.1 Rubio, CA. (Jun 2007). "Gastric duodenal metaplasia in duodenal adenomas.". J Clin Pathol 60 (6): 661-3. doi:10.1136/jcp.2006.039388. PMC 1955048. PMID 16837629. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1955048/.
  20. Lim, CH.; Cho, YS. (Jan 2016). "Nonampullary duodenal adenoma: Current understanding of its diagnosis, pathogenesis, and clinical management.". World J Gastroenterol 22 (2): 853-61. doi:10.3748/wjg.v22.i2.853. PMID 26811631.

External links

Review article(s)