Chapter 7 - Stomach & Duodenum

Question 1

What are the three zones of the stomach?

Answer 1

Cardia

Fundus/body

Antrum

Question 2

Distinguish between antral and oxyntic mucosa.

Answer 2

Antral: Loosely packed, mucinous glands which occupy about half of the epithelial thickness.

Oxyntic: Tightly packed, with parietal (pink) and chief (purple) cells, which occupy 3/4 of the epithelial thickness

Question 3

Which endocrine cells can be seen in the gastric body and antrum?

How can they be stained?

Answer 3

Body: Enterochromaffin-like cells

Antrum: Mixed gastrin, enterochromaffin, somatostatin.

All should stain for chromogranin.

Question 4

What color is normal stomach, generally?

What would goblet cells represent?

Answer 4

Pink; purple/blue indicates inflammation.

Intestinal metaplasia, a marker of chronic irritation.

Question 5

What mucosal histology does gastric cardia feature?

What endocrine cells does it feature?

Answer 5

Antral, or at least very similar to it.

No endocrine cells are seen.

Question 6

What inflammatory cells are OK in the stomach? Which indicate pathology?

Answer 6

Some lymphoplasmacytic or eosinophilic infiltrate is okay.

Dense lymphoplasmacytic infiltrate = chronic gastritis

Neutrophils = acute gastritis

Question 7

Describe the morphologic appearance of H. Pylori gastritis.

How can the organisms be visualized?

Answer 7

Neutrophils, chronic gastritis, and lymphoid follicles. Rod organisms in the pit lumens or on the surface of crypts.

Visible on H&E but better seen on diff-quik or giemsa. IHC?

Question 8

What causes MALT lymphoma in the stomach?

How does it appear?

Answer 8

Chronic H. Pylori infection.

Sheets of monocytoid B cells (fried egg-like) and lymphoepithelial lesions.

Question 9

Describe the appearance of foveolar hyperplasia. What does it represent?

Answer 9

Papillary and corkscrewed surface and pits due to proliferation of surface mucin cells. The mucin cells themselves lose mucin.

Represents chemical irritation, usually from bile or NSAIDs.

Question 10

What are two forms of atrophic gastritis? How do they appear?

What should atrophy be accompanied by?

Answer 10

H. Pylori gastritis: Loss of glands in setting of active chronic gastritis and intestinal metaplasia with pit abscesses

Autoimmune gastritis: Loss of parietal cells with compensatory G-cell hyperplasia.

Atrophy should be accompanied by intestinal metaplasia and inflammation.

Question 11

How does MALT lymphoma usually appear? What stains are helpful?

Answer 11

Usually monocytoid in appearance.

CD20+, CD43+ (also stains T-cells, subtract the CD3+ cells).

Question 12

Describe the appearance of gastric ulcers.

How can reparative glands be distinguished from carcinoma?

Answer 12

Full-thickness defect of epithelium down to the muscularis with fibrinopurulent exudate.

Reparative glands have small, reactive nuclei, in a streaming parallel arrangement.

Question 13

Name several causes for gastric ulcers.

Answer 13

Cancer

H. Pylori

NSAIDs, chemical injury

Burns

Severe stress

Question 14

Name 3 gastric polyps and describe their appearances.

Answer 14

Fundic gland polyp: Oxyntic mucosa with cystically dilated glands. Sporadic in older patients.

Hyperplastic polyps: Elongated, cystic with mild inflammation in a background of gastritis.

Adenomas: Neoplastic and dysplastic nodule, can be gastric-type (benign) or intestinal (eg TA)

Question 15

How does dysplasia in the stomach appear?

Answer 15

Like in the colon; hyperchromatic and pleomorphic with high N:C ratio and crowding/pseudostratification.

Question 16

Describe the appearance of intestinal-type gastric adenocarcinoma.

Answer 16

Associated with atrophy and intestinal metaplasia, usually quite easy to spot.

Question 17

Describe the appearance of diffuse-type gastric adenocarcinoma.

Answer 17

Signet-ring (foamy, macrophage-like) cells that infiltrate through the entire stomach causing linitis plastica.

Question 18

What lesions can be found in the gastric submucosa?

Answer 18

Heterotopic pancreas

GIST

Leiomyomas

Carcinoids

Question 19

What cells do GISTs arise from?

How can they be distinguished from leiomyomas?

From what conditions can carcinoids arise?

Answer 19

GIST arises from the interstitial cell of Cajal

Immunostaining for c-KIT and not smooth muscle markers

Sporadic in response to autoimmune gastritis, or in association with MEN syndromes

Question 20

What are some indications for duodenal biopsies?

Answer 20

Gastritis / duodenitis

Ulcers

Malabsorption

Mass lesions

Question 21

Describe the normal histologic appearance of duodenum.

Answer 21

Narrow villi with intestinal-type epithelium and inflammatory infiltrate. Submucosal Brunner’s glands.

Question 22

What is Chronic peptic duodenitis? Describe its morphology.

Answer 22

As a response to gastritis and acid hypersecretion, the duodenum may undergo gastric metaplasia. Also can have Brunner’s gland hyperplasia (mucosal!), inflammation, and ulceration.

Question 23

What is the classic picture of celiac disease?

Why will you rarely see this?

Answer 23

Flattened mucosa with total loss of villi and a low cuboidal epithelium.

Many people without disease are being biopsied because of serology, and those who have the disease often control their gluten intake, reducing the phenotype.

Question 24

What infections can appear in the duodenum, and how do they appear?

Answer 24

H. Pylori

Giardia (hides in luminal debris)

MAC (foamy histiocytes in the lamina propria)

Whipple’s disease (foamy histiocytes in the lamina propria! PAS+ granules and G+ rods)

Question 25

What tumors can be seen in the duodenum?

Answer 25

Tubular adenomas

Carcinoid tumors

Lymphoma (usually MALT type)

Question 26

Answer 26

Left: Oxyntic mucosa, with parietal and chief cells (arrow)

Right: Antral mucosa, with mucinous glands (arrow) and foveolar epithelium (arrowhead)

Question 27

Answer 27

H. Pylori gastritis

Arrow: Dens inflammatory infiltrate in the lamina propria

Arrowheads: Neutrophils in the surface epithelium (active)

Question 28

Answer 28

Chemical gastritis

Edematous lamina propria with corkscrewed hyperplastic glands (arrowhead) and thin strands of smooth muscle (arrow)

Question 29

Answer 29

Autoimmune gastritis

1. Intestinal metaplasia
2. Replacement of glands by mucinous antral-type
3. Residual oxyntic mucosa

Question 30

Answer 30

MALT lymphoma

Sheets of lymphocytes dissecting into muscle (arrow)

Inset: Lymphoepithelial lesions with destruction of glands by lymphocytes

Question 31

Answer 31

Reparative changes in an ulcer

Arrow: Glands streaming in parallel with normal nuclear size.

Question 32

Answer 32

Fundic gland polyp

Note oxyntic-type glands with some cystic dilation (circle)

Question 33

Answer 33

Hyperplastic polyp

Arrow: Corkscrew glands and hyperplastic foveolar epithelium.

Question 34

Answer 34

Signet ring carcinoma

Circle: Signet ring cell with large vacuole

Arrowheads: Additional infiltrating cells with large hyperchromatic nuclei.

Question 35

Answer 35

Chronic peptic duodenitis

Arrow: Gastric metaplasia

Arrowhead: Chronic inflammation and brunner’s gland hyperplasia

Question 36

Answer 36

Celiac disease

Note blunted villi, lamina propria inflammation (arrow), and intraepithelial lymphocytes (arrowhead)

Question 37

Answer 37

Duodenal adenoma

Arrow: Low grade dysplasia with crowded hyperchromatic nuclei

Arrowhead: Normal duodenal mucosa