Stomach

Stomach is an important organ for pathologists. It is often inflamed and may be a site that cancer arises from. Gastroenterologists often biopsy the organ. Surgeon take-out the organ. It connects the esophagus to the duodenum. An introduction to gastrointestinal pathology is in the gastrointestinal pathology article.

Normal stomach

Gross anatomy

• Cardia - first part of the stomach; joins with esophagus.
• Fundus - superior portion - not attached directly to the esophagus.
• Body - contains parietal cells.
• Pylorus - distal (think pyloric stenosis); it joins with the duodenum.
  • AKA antrum.

Image

• 

  Stomach anatomy (WC)

Microscopic

Foveolar cells versus intestinal goblet cells

• Intestinal goblet cells - clear mucin.
• Foveolar cells - eosinophilic contents.

Stomach versus intestine

A tabular comparison:

Feature	Intestine	Stomach
Spacing	Goblets cell - spaced	Foveolar cells - beside one another
Morphology of epithelial cells	columnar	tall columnar (Champagne flute)
Vesicle at luminal surface	touching/small opening	wide open
PAS-D	-ve (???)	+ve
Villin stain	+ve	-ve
Images	Tubular adenoma - goblet cells on right of image (WC)	Gastric biopsy (microscopy-uk.org.uk), Stomach with cancer - PAS (WC), Stomach (WC)

Notes:

• Intraepithelial lymphocytes in the gastric mucosa have a clear halo around 'em.
• Memory device: Folveolar cells have friends, i.e. they are close to other foveolar cells.

Gastric antrum versus gastric body

Cell	Body	Antrum	Histology	Image
Parietal cell	abundant	few or none	parietal cells: intensely eosinophilic cytoplasm	[1], [2]
Chief cell	present	absent	chief cells: basophilic cytoplasm, IHC: +ve for pepsinogen I	[3]
G cell	absent	present	fried egg appearance (clear cytoplasm, round nucleus); look at high power - usu. middle 1/3 of gland, IHC: +ve for gastrin.	[4]
Surface	flat	blunted villi	antrum is somewhat duodenum-like	body - flat
Gastric glands / mucosa	thick	thin	not so useful for discrimination	body - thick, body & antrum

Notes:

• G cells may superficially resemble intraepithelial lymphocytes.
  • G cell nucleus is usu. perfectly round and slightly larger (diameter of 12 micrometers?) than a lymphocyte nucleus (diameter ~ 9-10 micrometers?).

Sign out

Short version

STOMACH, BIOPSY:
- BODY AND ANTRAL-TYPE GASTRIC MUCOSA WITHIN NORMAL LIMITS.

STOMACH, BIOPSY:
- BODY AND ANTRAL-TYPE GASTRIC MUCOSA WITHIN NORMAL LIMITS.
- NEGATIVE FOR HELICOBACTER-LIKE ORGANISMS.

STOMACH, BIOPSY:
- ANTRAL-TYPE GASTRIC MUCOSA WITHIN NORMAL LIMITS.
- NEGATIVE FOR HELICOBACTER-LIKE ORGANISMS.

Long version

STOMACH, BIOPSY:
- BODY/ANTRAL-TYPE GASTRIC MUCOSA.
- INFLAMMATION: ABSENT.
- ATROPHY: ABSENT.
- INTESTINAL METAPLASIA: ABSENT.
- HELICOBACTER-LIKE ORGANISMS: NOT IDENTIFIED WITH ROUTINE STAINS.
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

Sleeve gastrectomy

• Indication: morbid obesity.

STOMACH, GREATER CURVE, SLEEVE GASTRECTOMY:
- STOMACH WALL WITHIN NORMAL LIMITS.

Introduction

Useful stains for stomach

• Cresyl violet stain - used to find H. pylori.
• Alcian blue stain - used to find mucin which is present in intestinal metaplasia
  • Other mucins stains: mucicarmine, PAS, PASD (doesn't stain glycogen)

Things to look for...

• Parietal cells (indicate you're in the body of the stomach) - pink (eosinophilic) cytoplasm.
  • Lack of parietal cells -- DDx: Bx of antrum (pylorus), Bx of cardia, pernicious anemia.
• Goblet cells = intestinal metaplasia.
• Architectural distortion of gastric glands - suspect cancer.
• Signet ring cells = (usually) gastric carcinoma.
  • Can be very easy to miss in some biopsies.
• Inflammation + small bacteria = suspect H. pylori gastritis.

Some patterns

Gastric atrophy

General

• Has a wide differential diagnosis.

Microscopic

Can take three general forms:

1. Intestinal metaplasia - see intestinal metaplasia section.
2. Pseudopyloric metaplasia; gastric body looks like gastric antrum.
   • Characterized by foveolar hyperplasia.
3. Cell loss without replacement.
   • Clue is deep inflammation in the body.

Plasma cells in the stomach

DDx of plasmacytosis:

• Plasma cell neoplasm.
• Syphilis.
• Chronic gastritis.

Granulomatous gastritis

• Usual DDx of granulomatous disease (see Basics article):
  • DNF AAII:
    • Drugs, Neoplasms, Foreign body, Autoimmune, Allergic, Infectious, Idiopathic.

Important ones:

• Autoimmune - Crohn's disease.
• Infectious - Tuberculosis.
• Idiopathic - Sarcoidosis.

Non-neoplastic disease

Peptic ulcer disease

• Abbreviated PUD.

For duodenal manifestations see Peptic duodenitis.

General

• Benign.

Complications:

• Hemorrhage.
• Obstruction.
• Perforation - can be fatal.

Etiology - typically:

• Helicobacter pylori.

Gross

Features:

• Typically in the duodenum; duodenum:stomach = ~4:1.
  • Epithelial defect with punched-out edges (suggestive of a benign process).

Note:

• Heaped edges - suggestive of cancer.

Image:

• Gastric ulcer (WC).

Microscopic

Features:

• Loss of epithelium.
• Inflammation.
• +/-Helicobacter organisms - see Helicobacter gastritis.

Gastritis

Etiology

A specific cause is uncommonly identified histologically.

Gastritis causes:

• Infectious:
  • H. pylori infection.
  • Tuberculosis.
  • Salmonellosis.
  • CMV.
• Endocrine-related:
  • Pernicious anemia.
  • Diabetes mellitus - gastric atony.
• Trauma, e.g. NG tube.
• Vascular, ischemia.
• Autoimmune:
  • Crohn's disease.
• Toxins:
  • Alcohol.
  • Medications, especially NSAIDs.
  • Uremia.
  • Smoking (heavy).
• Radiation.

Endoscopic appearance

• Erythematous.

Microscopic

• Inflammatory cells - see below.

Acute gastritis

• AKA active gastritis.

Features:

• Neutrophils - especially when intraepithelial.

Focal active gastritis

DDx:

1. Drugs, esp. NSAIDs.
2. Infectious.
3. Inflammatory bowel disease.

Chronic gastritis

Features:

• Plasma cells (in lamina propria).
  • Various criteria:
    1. Two plasma cells kissing, i.e. two plasma cells touching/overlapping.
    2. Three is a crowd, i.e. three plasma cells in close proximity.

Note:

• Approximately 20% of cases with an inflamed cardia will have intestinal metaplasia.

General

The DDx is limited:

1. Helicobacter gastritis.
2. Celiac disease.
3. NSAIDs.^{[citation needed]}
4. Idiopathic.
5. HIV/AIDS.

Microscopic

Features:

• 25 lymphocytes / 100 epithelial cells.

Sydney criteria for gastritis

A bunch of pathologists in Sydney came-up with criteria... and these were revised in Houston.

Classification

Updated Sydney classification:

Feature	Non-atrophic Helicobacter	Atrophic Helicobacter	Autoimmune
Inflammation pattern	antral or diffuse	antrum & corpus, mild inflammation	corpus only
Atrophy & metaplasia	nil	atrophy present, metaplasia at incisura	corpus only

Notes:

• Corpus = gastric body.
• Incisura = angular incisure, incisura angularis (Latin) - notched transition point on lesser curvature of the stomach between pylorus and body.

Severity

The Sydney group suggests grading severity with the following language:

• Mild.
• Moderate.
• Marked.

These terms are applied to the parameters described in a biopsy. The Sydney criteria lists H. pylori, neutrophils, mononuclear cells, antrum (atrophy), corpus (atrophy) and intestinal metaplasia. The paper that discusses this also give a visual analogue scale.

Parameters & Severity (adapted from Dixon et al.):

Feature	Mild	Moderate	Marked
H. pylori	few touching	many touching	piles
Neutrophils	few	bunches	crowded
Mononuclear cells	not touching	kissing	partying

Sign out

Mild chronic

STOMACH, BIOPSY: 
- BODY AND ANTRAL-TYPE GASTRIC MUCOSA WITH MILD CHRONIC INFLAMMATION. 
- NEGATIVE FOR HELICOBACTOR-LIKE ORGANISMS. 
- NEGATIVE FOR INTESTINAL METAPLASIA. 
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

Moderate chronic active

STOMACH, BIOPSY: 
- BODY AND ANTRAL-TYPE GASTRIC MUCOSA WITH MODERATE CHRONIC ACTIVE INFLAMMATION. 
- NEGATIVE FOR HELICOBACTOR-LIKE ORGANISMS. 
- NEGATIVE FOR INTESTINAL METAPLASIA. 
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

Micro

The sections show gastric body type mucosa with small clusters of plasma cells. There are no intraepithelial neutrophils. Goblet cells are not identified. The epithelium matures normally to the surface. No Helicobacter organisms are seen.

Helicobacter gastritis

• Often abbreviated HP.

General

• Several Helicobacter species can cause gastritis:
  • Helicobacter pylori - most common.
  • Helicobacter heilmannii.

Epidemiologic associations - Helicobacter infections are associated with:

• Gastritis.
• Peptic ulcers.
• Cancer.
  • Carcinoma.
  • MALT lymphoma.

Gross

• Thickened gastric folds.
• Erythema.

Microscopic

Features:

• Helicobacter organisms - key feature.
  • Helicobacter pylori:
    • Usually have v-shape (seagull-like shape).
      • May have a curved shape (comma-like shape) or U-shape.
  • Helicobacter heilmannii:
    • Corkscrew appearance.
• Inflammation - usually moderate chronic active.
  • Clusters of (lamina propria) plasma cells.
  • Neutrophils, numerous, classically intraepithelial.

Tips:

1. One needs to look at 400x magnification. Even at 400x they are possible to miss.
   • Helicobacter are damn small. They are smaller than the nucleus of the gastric foveollar cell.
2. Look for mucus - they preferentially reside there.
   • This is usually close to the opening of the gastric pits.
3. Helicobacter are found in groups. When you see several that are the same size and shape you can be sure they are real.

Notes:

• Helicobacter can be in antrum and/or body.
• Helicobacter don't like the intestinal mucosa or mucosa that has undergone intestinal metaplasia; you're less likely to find 'em adjacent to it. In general, Helicobacter is uncommon in the context of a case with IM... but common enough that one still ought to look for it.
• May be associated with G-cell hyperplasia.

DDx:

• Dirt - material has a variable size.
• Contamination from oropharynx - bacilli straight, not associated with gastric mucosa.

Images:

• H. pylori - IHC (WC).
• Helicobacter gastritis:
  • Gastritis due to HP (WC).
  • HP visible (WC).
• Set of images - HP gastritis (WC).
• Helicobacter heilmannii (bmj.com).

Stains

• Cresyl violet stain - background and organisms blue.
• Warthin-Starry stain - background yellow, organisms black.

IHC

• Helicobacter pylori IHC stain +ve.

Note:

• Reportly also stains Helicobacter heilmannii.

Sign out

Body

STOMACH, BIOPSY:
- BODY-TYPE MUCOSA WITH MODERATE CHRONIC ACTIVE GASTRITIS.
- ABUNDANT HELICOBACTER-LIKE ORGANISMS PRESENT.
- NEGATIVE FOR INTESTINAL METAPLASIA.
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

Body

STOMACH, BIOPSY:
- ANTRAL-TYPE MUCOSA WITH MODERATE CHRONIC ACTIVE GASTRITIS.
- ABUNDANT HELICOBACTER-LIKE ORGANISMS PRESENT.
- NEGATIVE FOR INTESTINAL METAPLASIA.
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

Micro

The sections show antral-type gastric mucosa with abundant lamina propria plasma cells and focal intraepithelial neutrophils. Cocci and bacilli are present. Some of the bacilli are Helicobactor-like. The epithelium matures normally to the surface. No goblet cells are identified.

Intestinal metaplasia of the stomach

• AKA gastric intestinal metaplasia.
• Abbreviated IM.

General

• Often part of surgical pathology report, e.g. "negative for intestinal metaplasia" or "intestinal metaplasia present".
• May be associated with Helicobacter spp. infection -- though Helicobacter don't like intestinal type mucosa, i.e. H. pylori are not typically found in regions with intestinal metaplasia.
• May be reversible - some epidemiological evidence.
• Associated with gastric carcinomas of Lynch syndrome; however, surveillance may not be worthwhile.

Significance:

• Moderate risk increase for carcinoma; risk less than for Barrett's esophagus.
  • Odds ratio for corpus (~5.8x) higher than antrum (2.3x) when compared to individuals without IM.

Microscopic

Features:

• Goblet cells are present in the stomach - key feature.
  • In H&E sections the vacuole often stains light grey.
  • Foveolar epithelium should be present in the same fragment.
• +/-Paneth cells - deep in the glands.
  • Very rarely present.
  • Very uncommon in isolation.

Notes:

• Intestinal metaplasia (IM) is occasionally subdivided:
  • Complete IM = goblet cells and (intestinal) brush border.
  • Incomplete IM = mucus vacuoles of various sizes, no (intestinal) brush border.
• Goblet cells metaplasia starts in the neck region of the gastric glands.

DDx:

• Normal small bowel mucosa - no foveolar epithelium present.
• Gastric dysplasia, intestinal type.

Image:

• Intestinal metaplasia in the stomach - crappy quality (WC).

Stains

• Alcian blue (pH 2.5)/PAS +ve.
  • May be used to divide into complete (type I) and incomplete (type II).
• Alican blue stain +ve.^{[citation needed]}

Image:

• Barrett's mucosa - Alcian blue stain (WC).

IHC

• CDX2 +ve (-ve in normal stomach).
  • Strong assoc. with Helicobacter gastritis as well as IM.

Others:

• Lysozyme +ve - marks paneth cells.

Sign out

STOMACH, BIOPSY:
- BODY-TYPE MUCOSA WITH INTESTINAL METAPLASIA, FOCAL.
- MINIMAL CHRONIC GASTRITIS (BODY OF STOMACH).
- NEGATIVE FOR HELICOBACTER-LIKE ORGANISMS.
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

STOMACH, BIOPSY:
- ANTRAL-TYPE MUCOSA WITH INTESTINAL METAPLASIA, EXTENSIVE.
- MILD CHRONIC (ANTRAL) GASTRITIS.
- NEGATIVE FOR HELICOBACTER-LIKE ORGANISMS.
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

STOMACH, BIOPSY:
- SUPERFICIAL GASTRIC MUCOSA WITH EXTENSIVE INTESTINAL METAPLASIA AND MODERATE
  CHRONIC INACTIVE INFLAMMATION.
- NEGATIVE FOR HELICOBACTOR-LIKE ORGANISMS.
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

Inflammatory bowel disease & the stomach

See inflammatory bowel disease.

• Histopathologic findings are usually non-specific.
• Conventional thinking was upper GI involvement = Crohn's disease; this is changing.

Microscopic

Features:

• Focal inflammation.
  • Common finding - non-specific.
• +/-Granulomas.

Miscellaneous

This is a grab bag of stuff seen in the stomach. Some of it is quite rare.

Gastric antral vascular ectasia

• Abbreviated GAVE.
• AKA watermelon stomach - due to characteristic endoscopic appearance.

General

• Lesion of the antrum - due to dilated capillaries.

Gross/endoscopic appearance

• Linear red streaks in antrum - oriented toward the pyloric valve... vaguely resembles a watermelon.

Endoscopic images:

• Watermelon stomach (pubmedcentral.nih.gov).
• GAVE (WP).

Microscopic

Features:

• Fibrin thrombi - characteristic feature.
• Dilated capillaries in lamina propria.
• +/-Foveollar hyperplasia.

DDx:

• Portal hypertensive gastropathy - predominantly in the gastric body, usu. associated with cirrhosis, do not have fibrin thrombi.

Images:

• GAVE - intermed. mag. (WC).
• GAVE - very high mag. (WC).
• GAVE - two thrombi - very high mag. (WC).

Sign out

STOMACH, BIOPSY: 
- GASTRIC ANTRAL VASCULAR ECTASIA WITH FOVEOLAR HYPERPLASIA.
- MILD CHRONIC ACTIVE ANTRAL GASTRITIS.
- NEGATIVE FOR INTESTINAL METAPLASIA. 
- NEGATIVE FOR DYSPLASIA. 
- NEGATIVE FOR HELICOBACTER ORGANISMS.

Micro

The sections show antral-type gastric mucosa with dilated lamina propria blood vessels and intravascular fibrin thrombi. There is mild foveolar hyperplasia. Numerous neutrophils are present between the foveollar cells and within the lamina propria. Several large clusters of plasma cells are present in the lamina propria.

Reactive gastropathy

• Abbreviated RG.
• AKA chemical gastropathy, incorrectly referred to as chemical gastritis (see below).

General

• May be seen in the context of a previous resection/surgical reconstruction, e.g. Billroth II.

Epidemiology

General assocations:

• Increases with age.

Etologic factors - associated with:

• Excess acid.
• EtOH.
• Bile.
• H. pylori.
• Drugs:
  • Iron (brown pigment on histology).
  • NSAIDs - synergistic effect with corticosteroids.

Drugs that cause erosions and/or ulcers -- adapted from Genta:

Drug	Comment	Indication for Rx
NSAIDs	common cause	pain, reduce cardiovascular risk
Corticosteroids	synergistic effect with NSAIDs	rheumatologic diseases + others
Potassium (KCl)	common cause	renal failure
Bisphophonates	uncommon cause	osteoporosis
Ferrous sulfate	very common if symptomatic	iron deficiency anemia
Chloroquine	uncommon	only in the context of malaria
Sodium polystyrene sulfonate (Kayexalate)	rare	renal failure patients

Relation to gastritis

• May mimic a (true) gastritis symptomatically and visually in an endoscopic examination.
• "Chemical gastritis" is misnomer. Etymologically, the -itis in gastritis, implies an inflammatory process. Chemical gastropathy is not (predominantly) an inflammatory process.
  • This type of confusion is not uncommon. Steatohepatitis is another example of this; it is not a process with significant inflammation yet, confusingly, carries the -itis ending.

Gross/endoscopic

Features:

• Antral erythema +/- erosions.
• +/-Bile.

Microscopic

Features - triad:

1. Foveolar hyperplasia.
   • Tortuosity of glands in the "neck" region of the gastric glands.
   • Associated with "mucin depletion" - cytoplasm not clear -- as is usual.
2. Smooth muscle fibre hyperplasia.
   • Abundant eosinophilic lamina propria.
3. Scant acute & chronic inflammatory cells.

Additional features.

• +/-Edema.
• +/-Erosions.

Notes:

• Triad rarely present; mild inflammation common.

DDx:

• Amyloidosis.
• Collagenous gastritis.
• Hyperplastic polyp of the stomach.

Images

• 

  RG - low mag. (WC/Nephron)

• 

  RG - high mag. (WC/Nephron)

Sign out

STOMACH, BIOPSY:
- ANTRAL-TYPE GASTRIC MUCOSA WITH REACTIVE GASTROPATHY, SEE COMMENT.
- NEGATIVE FOR INTESTINAL METAPLASIA.
- NEGATIVE FOR HELICOBACTER-LIKE ORGANISMS.
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

COMMENT:
This nonspecific finding may be due to a number of causes, including 
medications (especially NSAIDs), alcohol and bile reflux.

Not well-developed

STOMACH, BIOPSY:
- BODY-TYPE GASTRIC MUCOSA WITHIN NORMAL LIMITS.
- ANTRAL-TYPE GASTRIC MUCOSA WITH SMOOTH MUSCLE HYPERPLASIA AND 
  FOCAL GASTRIC GLAND TORTUOSITY, SEE COMMENT.
- NEGATIVE FOR INTESTINAL METAPLASIA.
- NEGATIVE FOR HELICOBACTER-LIKE ORGANISMS.
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

COMMENT:
These findings are suggestive of a reactive gastropathy; however, gland 
corkscrewing is not evident.

STOMACH, BIOPSY:
- ANTRAL-TYPE GASTRIC MUCOSA WITH PROMINENT SMOOTH MUSCLE, OTHERWISE WITHIN NORMAL
LIMITS.
- NEGATIVE FOR INTESTINAL METAPLASIA.
- NEGATIVE FOR HELICOBACTER-LIKE ORGANISMS.
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

Autoimmune metaplastic atrophic gastritis

Pernicious anemia redirects here.

• AKA autoimmune gastritis.

General

• Pathology: loss of parietal cells, gastric atrophy, macrocytic anemia.
• Etiology: autoimmune.

Diagnosis based on serology for antibodies to:

• Parietal cells.
• Intrinsic factor.

Others:

• Gastrin level (increased).
  • Normal < 100 pg/mL.

Note:

• Parietal cells produce intrinsic factor (important for vitamin B12 absorption) and hydrogen chloride, i.e. stomach acid.

Microscopic

Features:

• Corpus predominant inflammation - usu. moderate or severe - key feature.
• Loss of parietal cells.
• Increased G cells in the antrum.
  • Produce gastrin to stimulate the (missing) parietal cells.

DDx:

• Gastric neuroendocrine tumour.

Notes:

• Compare with other types of gastric atrophy.

IHC

Features:

• Chromogranin A +ve (demonstrates nodular enterochromaffin-like cell hyperplasia).
• Gastrin -ve (body of stomach).
  • +ve in antrum.

Images:

• Autoimmune gastritis - chromogranin A (nih.gov).
  • Findings may be seen in hypergastrinemia and nodular enterochromaffin cell-like (ECL) hyperplasia.

Sign out

STOMACH, BIOPSY:
- SEVERE CHRONIC ACTIVE GASTRITIS WITH EXTENSIVE INTESTINAL METAPLASIA.
- NEGATIVE FOR HELICOBACTER-LIKE ORGANISMS.
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

COMMENT:
Parietal cells are not apparent on the H&E stained sections. Immunostains show 
rows of Chromogranin A positive cells and a lack of gastrin staining.  

These findings suggest an autoimmune gastritis; correlation with blood work 
is suggested.

Collagenous gastritis

General

• Very rare.
• Associated with collagenous colitis.

Microscopic

Features:

• Eosinophilic material (collagen) expands lamina propria.
  • Band of collagen must be ~thick as RBC diameter.
    • Proven by trichrome stain that highlights collagen.

Gastritis cystitis profunda

• AKA Gastritic cystica profunda.^{[citation needed]}

General

• May be associated with glandular proliferation as well. (???)
• Super rare.
• Similar to cystitis cystica.

Microscopic

Features:

• Cystic spaces lined by foveolar epithelium.

Ménétrier's disease

• AKA diffuse foveolar cell hyperplasia.

General

• Super rare.
• Increased risk of gastric adenocarcinoma.

Clinical:

• Classical: nausea, emesis, abdominal pain and peripheral edema.
  • Emesis (intractable) - most important.

Other:

• Gastric mass (may mimic cancer).
• Hypochlorhydria.
• Protein loss (hypoalbuminemia) - leads to peripheral edema.

Epidemiology:

• Men > women.
• Adults usually 50s.
• Associated with ulcerative colitis.

Treatment:

• EGFR inhibitors.
• Gastrectomy.

Gross

• "Bag of worms" appearance - very thick gastric folds.

Microscopic

Features:

• Foveolar cell hyperplasia - key feature.
• Decreased parietal cells.
• +/-Inflammation.

DDx:

• Cronkhite-Canada syndrome.
• Hyperplastic polyp of the stomach.

Images:

• Ménétrier's disease - crappy images (upmc.edu).

Gastric xanthoma

• Abbreviated GX.
• AKA xanthelasma.
• AKA stomach lipidosis.

General

• Uncommon.
• Benign.

Gross/endoscopic

• Yellowish nodule or plaque.
  • Classically lesser curvature and antrum.

Microscopic

Features:

• Collections of gastric lamina propria with lipid-laden macrophages.

DDx:

• Signet ring cell carcinoma.
• Whipple disease.
• MAC infection.

Images:

• GX - low mag. (flickr.com).
• GX - high mag. (flickr.com).

IHC

• CD68 +ve.
• Panker (AE1/AE3) -ve.

Gastric ischemia

Gastric necrosis redirects here.

General

• Rare.
• May arise due to:
  • Small bowel obstruction.
  • Therapeutic embolization.

Microscopic

Features:

• +/-Pseudomembrane formation.
• Necrosis of the epithelium lining the gastric pits.

Image:

• Gastric necrosis (thieme-connect.com).

Portal hypertensive gastropathy

• Abbreviated PHG.

General

• Due to portal hypertension.
  • Usually secondary to liver cirrhosis which is typically due to alcoholism.
    • Reported in approximately 65% of cirrhotics with portal hypertension in one paper.

Gross

Features:

• Mosaic-like pattern.
  • May be referred to as snakeskin-like pattern.
  • Usu. body of stomach.
• +/-Red spots.

Note:

• May mimic eosinophilic gastritis.

Images

• 

  PHG. (WC/Samir)

Microscopic

Features:

• Dilated capillaries in the submucosa (prominent) and to a lesser extent in the lamina propria - key feature.

Notes:

• May be associated with hyperplastic-like polyps.
  • Subepithelial granulation tissue and vascular proliferation.
• Findings in mucosal biopsies are often nonspecific, i.e. not diagnostic.

DDx:

• Gastric antral vascular ectasia - have thrombi in the dilated blood vessels.

Sign out

STOMACH, BIOPSY:
- ANTRAL-TYPE AND BODY-TYPE GASTRIC MUCOSA WITH PROMINENT CAPILLARIES 
AND MODERATE CHRONIC INACTIVE INFLAMMATION.
- NEGATIVE FOR HELICOBACTER-LIKE ORGANISMS.
- NEGATIVE FOR INTESTINAL METAPLASIA.
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

COMMENT:
No fibrin thrombi are seen.  The findings are compatible with portal hypertension.
Clinical correlation is required.

Gastric polyps

Similar to colonic polyps - see intestinal polyps.

DDx polyp (similar to colon & rectum):

• Hyperplastic - most common, characterised by abundant elongated foveola + glands.
• Hamartomatous - weriod stuff.
• Inflammatory fibroid polyp - inflammation, myxoid stroma.
• Fundic gland polyp - cystic dilation, flat epithelium.
• Gastric adenoma - polypoid gastric dysplasia.

Inflammatory fibroid polyp

Main article: Inflammatory fibroid polyp

Hyperplastic polyp of the stomach

Main article: Hyperplastic polyp

• AKA gastric hyperplastic polyp.

General

• Benign.
• Most common gastric polyp.

Microscopic

Features:

• Abundant foveolar cells and elongated glands - key feature.
• +/-Gland dilation.

Negatives:

• No atypical nuclei.
• No hyperchromasia.
• No loss of pseudostratification.

Notes:

• No serrations - as in the colon.

DDx:

• Ménétrier's disease (hyperplastic hypersecretory gastropathy).
• Juvenile polyp - abundant lamina propria, dilated glands may have neutrophils.
• Peutz-Jeghers polyp - thick superficial muscle.
• Fundic gland polyp - doesn't have foveolar hyperplasia.

Images

• 

  Gastric hyperplastic polyp - low mag. (WC/KGH)

• 

  Gastric hyperplastic polyp - high mag. (WC/KGH)

www:

• Gastric hyperplastic polyp (flickr.com).
• Gastric hyperplastic polyp (flickr.com).

Fundic gland polyp

• Abbreviated FGP.

General

• Most common stomach polyp.
• Fundic location usually.
  • May be in the body.

Clinical significance

• Weak association with FAP (familial adenomatous polyposis).
• Associated with chronic proton pump inhibitors (PPI) use -- approximately 4x risk.

Notes:

• Animal studies suggested PPIs cause neuroendocrine tumours -- but this has not been found in humans.

Microscopic

Features:

• Polypoid shape (may not be appreciated on microscopy).
• Dilated gastric glands.
  • Flatted epithelial lining (consisting of normal foveolar epithelium) - key feature.

Notes:

• The presence of dysplastic changes should prompt consideration of FAP.

DDx:

• Hyperplastic polyp of the stomach - has foveolar hyperplasia, gland dilation may be present.

Image:

• Fundic gland polyp (ouhsc.edu).

Sign out

POLYP, STOMACH, BIOPSY:
- FUNDIC GLAND POLYP.
- NEGATIVE FOR INTESTINAL METAPLASIA.
- NEGATIVE FOR HELICOBACTER-LIKE ORGANISMS.
- NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.

Neoplastic

The spectrum from benign to malignant is divided into five:

1. Benign.
2. Indefinite for gastric epithelial dysplasia.
3. Low-grade gastric epithelial dysplasia.
4. High-grade gastric epithelial dysplasia.
5. Gastric carcinoma.

Gastric dysplasia

Gastric adenoma directs here.

• AKA gastric columnar dysplasia.

General

• Lesions that protrude into the lumen and are macroscopically apparent are known as: adenomas.
• Polypoid forms are grouped various ways.

Grading

Like in the colon - they are divided into:

• Low grade.
• High grade.

Subclassification

One subclassification:

• Intestinal: goblet cells or Paneth cells.
  • Not associated with FAP.
• Gastric: foveolar epithelium.
  • Associated with familial adenomatous polyposis (FAP).

Microscopic

• Histologic criteria similar to columnar dysplasia in the esophagus.
  • The threshold is much lower than in the colon and rectum.

Foveolar type

Features:

• Hyperchromasia at the surface - key feature.
• Cytoplasm with (shortened) champagne flute-like luminal aspect (apical mucin caps).
• Nuclear changes:
  • Hyperchromasia.
  • Enlargement.
• No intestinal metaplasia.

DDx:

• Gastric carcinoma.
• Reactive changes.

Intestinal type

Features - intestinal:

• Intestinal metaplasia.
• Hyperchromasia of cytoplasm.
• Nuclear changes:
  • Loss of nuclear polarity.
  • Increased NC ratio.
  • Elongation of nucleus and pseudostratification.

DDx:

• Gastric carcinoma.
• Reactive changes.
• Intestinal metaplasia.

Images

• 

  Gastric adenoma. (WC/KGH)

• 

  Gastric adenoma. (WC/KGH)

www:

• Gastric polyps - several images (sciencedirect.com).
• Gastric polyps - several images (achivesofpathology.org).

Grading

Low-grade gastric dysplasia

Features:

• Nuclear changes:
  • Nuclear crowding/pseudostratification with hyperchromasia.
  • Elongation of nuclei (cigar-shaped nuclei).
  • Nuclear stratification intact; nuclei close to the basement membrane.
• Architecture:
  • Focal irregularities in the glandular contours.

Negatives:

• No desmoplasia.
• No necrosis.
• No surface maturation.

DDx:

• Indefinite for dysplasia.
• High-grade gastric columnar dysplasia - see below.
  • The threshold is much lower than in the colon and rectum!

Images:

• Low-grade gastric columnar dysplasia - several images (upmc.edu).
• Gastric low-grade dysplasia (nih.gov).

High-grade gastric dysplasia

Features:

• Nuclear changes:
  • Round hyperchromatic nuclei.
  • Loss of normal nuclear stratification.
• Architecture:
  • Irregularities in the glandular contours.
  • Back-to-back glands.
  • Cribriforming of the glands.
  • +/-Necrosis.

Negatives:

• No desmoplasia.

DDx:

• Low-grade gastric columnar dysplasia.
• Gastric adenocarcinoma.

Images

• 

  High grade gastric dysplasia - low mag. (WC/Nephron)

• 

  High grade gastric dysplasia - very high mag. (WC/Nephron)

www:

• Gastric high-grade dysplasia - probably (nih.gov).
• Gastric high-grade dysplasia - probably (nih.gov).
• Gastric high-grade dysplasia (nih.gov).

Sign out

Indefinite for dypslasia

STOMACH, ANTRUM, BIOPSIES:
- ANTRAL-TYPE MUCOSA INDEFINITE FOR DYSPLASIA WITH MODERATE CHRONIC INFLAMMATION.
- EXTENSIVE INTESTINAL METAPLASIA.
- NEGATIVE FOR HELICOBACTER-LIKE ORGANSIMS.
- NEGATIVE FOR MALIGNANCY.

Intestinal type

 STOMACH, ANTRUM, BIOPSIES:
- ANTRAL-TYPE MUCOSA WITH FOCUS OF LOW-GRADE DYSPLASIA (INTESTINAL TYPE).
- EXTENSIVE INTESTINAL METAPLASIA.
- MODERATE CHRONIC INFLAMMATION.
- NEGATIVE FOR HELICOBACTER-LIKE ORGANSIMS.
- NEGATIVE FOR MALIGNANCY.

Foveolar type

 STOMACH POLYP, BIOPSY:
- ADENOMATOUS POLYP, FOVEOLAR TYPE.
- NEGATIVE FOR HIGH-GRADE DYSPLASIA. 
- NEGATIVE FOR HELICOBACTER-LIKE ORGANISMS.

Gastric neuroendocrine tumour

• AKA neuroendocrine tumour of the stomach.

General

• Behaviour dependent on the subtype.
• Uncommon.

Overview of subtypes

Divided into four types:

Tumour type	Relative prevalence	Multifocality	Tumour size	Typical location	Clinical	Other	Histology
Type 1	~75%	yes	small (5-10 mm)	body	benign typically, female:male ~ 4:1, 50-60 years	chronic atrophic gastritis - usu. autoimmune	WDNET, WDNEC
Type 2	rare	yes	small ~15 mm	body	aggressive, ~50 years old	assoc. MEN I, hyperchlorhydia	WDNEC, WDNET
Type 3	10-15%	no	small and large	variable location	aggressive if >2.0 cm, males > females	normal gastrin levels	WDNET
Type 4	extremely rare	no	large	variable location	aggressive (mets usu. at time of Dx), males > females	elevated gastrin d/t parietal cell dysfunction	PDNEC

Notes:

• WDNET = well-differentiated neuroendocrine tumour.
• WDNEC = well-differentiated neuroendocrine carcinoma.
• PDNEC = poorly-differentiated neuroendocrine carinoma.

Microscopic

See neuroendocrine tumours

Neoplastic rare

Gastric calcifying fibrous tumour

Main article: Calcifying fibrous tumour

Gastric cancer

• Gastrointestinal stromal tumour (GIST).
• Gastric adenocarcinoma.
• MALT lymphoma.

Gastric lymphoma

Main article: MALT lymphoma

General

• Associated with helicobacter infection.
• Usually MALT lymphoma (mucosa-associated lymphoid tissue lymphoma).

Microscopic

Features:

• Sheets of lymphoid cells.
• "Lymphoepithelial lesion" - gastric crypts invaded by a monomorphous population of lymphocytes.
  • Features:
    1. Cluster of lymphocytes - three cells or more - key feature.
       • Single lymphocytes don't count.
    2. Clearing around the lymphocyte cluster.
  • Associated with MALT lymphoma; however, not specific.

DDx:

• Reactive lymphoid hyperplasia.
• Syphilis.

IHC

• Panker -- most useful.

Others:

• CD3 (T cells) - scatter positivity.
• CD20 (B cells) +ve.
• CD138 (plasma cells).
• kappa, lambda -- often one is predominant, suggesting clonality.
• BCL2 +ve.

Treatment

• Triple therapy (two antibiotics, proton pump inhibitor (PPI)).
• Surgery - if triple therapy fails.

Review paper: PMID 16950858.

Hereditary gastric cancer

Several syndromes are associated with gastric cancer:

Disease	Gene	Histology	Other
Hereditary diffuse gastric cancer (HDGC) syndrome	CDH1 (E-cadherin)	diffuse - more specifically signet ring cell carcinoma	most important; assoc. invasive lobular carcinoma
Lynch syndrome	MSH2, MLH1, others	?	colorectal carcinoma, endometrial carcinoma
Familial adenomatous polyposis	APC	?	adenomatous polyps
Peutz-Jeghers syndrome	STK11	?	stomach hamartomas - not precursor
Li-Fraumeni syndrome	TP53 (p53)	?	AKA SBLA syndrome = sarcomas, breast, brain, leukemia, laryngeal, lung, adrenocortical carcinoma
Familial breast and ovarian cancer 2	BRCA2	?	?

Gastric adenocarcinoma

General

Epidemiology:

• Prognosis is often poor as it is discovered at a late stage.
• Higher prevalence in countries in the far east (e.g. Japan) - thought to be environmental, e.g. diet.

Risk factors:

• Associated with helicobacter infections, i.e. Helicobacter gastritis.
• Alcohol - heavy use.
• Genetic syndromes - see hereditary gastric cancer.

Note:

• Possible association with tobacco use - dependent on the study.

Treatment:

• Surgical excision.
  • Proximal tumours may require a complete gastrectomy as the stomach is innervated from its proximal part.

Classification

• Two different classification schemes.
  • Lauren - two types:
    • Intestinal type (mass forming).
    • Diffuse type (infiltrative).
  • WHO classification - 6 subtypes for adenocarcinoma:
    1. Papillary carcinoma.
    2. Tubular carcinoma.
    3. Mucinous carcinoma.
    4. Signet-ring carcinoma.
    5. Undifferentiated carcinoma.
    6. Adenosquamous carcinoma.

Lame memory device STOMACH:

• Signet ring, Tubular, Oh papillary, Mucinous, Adenosquamouas, Crappy High grade (Undifferentiated).

Gross

Location:

• Large carcinomas preferentially involve the lesser curvature.
• Ulceration with heaped (raised) edges.
  • Appearance of the typical intestinal type tumour.
• Diffuse wall thickening with loss of the rugae - called linitis plastica.
  • Typically due to diffuse carcinoma.

Main DDx of ulcer:

• Peptic ulcer disease - have a "punched-out" appearance: sharp edge, no granularity of surrounding mucosa.

Images:

• Linitis plastica - endoscopic image (WC).
• Ulcerating gastric carcinoma (WC).
• Ulcerating gastric carcinoma (WC).

Microscopic

Features - variable, either of the two following:

1. "Typical adenocarcinoma":
   • Gland-forming lesion that infiltrates into the lamina propria or beyond.
   • Nuclear pleomorphism - common.
2. +/-Signet ring carcinoma.
   • Scattered single cells in the lamina propria or beyond with:
     • Abundant cytoplasm containing one large (mucin-filled) vacuole.
     • A peripheral nucleus (displaced by the vacuole).

DDx:

• Gastric xanthoma - may mimic signet ring cell carcinoma.

Images:

• WC:
  • Gastric adenocarcinoma (WC).
  • SRC - breast (WC).
  • Gastric SRC - PAS stain (WC).
• www:
  • Gastric adenocarcinoma - several images (upmc.edu).

Stains

• Mucicarmine +ve.

IHC

• CK7 +ve.
• CK20 -ve, occasionally +ve.

Others:

• p53 +ve in upto 75% of cases.

Molecular

• May have HER2 over expression - more common in intestinal-type tumours.
  • Poor prognosis - like in breast cancer.
  • Scoring system different than in breast cancer - complete membrane staining is not required.

Sign out

Biopsy

Intestinal type

STOMACH, BIOPSY:
- INVASIVE ADENOCARCINOMA, INTESTINAL TYPE, MODERATELY DIFFERENTIATED.
- Gastric mucosa with moderate chronic active inflammation and extensive
   intestinal metaplasia.
- Benign small bowel mucosa with erosions.

Diffuse type

STOMACH, BIOPSY:
- INVASIVE ADENOCARCINOMA, DIFFUSE TYPE.

COMMENT:
A pankeratin immunostain demonstrates single (infiltrating) epithelial cells in the
lamina propria.

Micro

The tumour consists of single cells with abundant foamy-appearing cytoplasm and eccentric nuclei with mild nuclear atypia.

See also

• Esophagus.
• Duodenum.
• Granulation tissue.
• Intestinal polyps.