Lab 1

Question 1

Main differences squamous cell carcinoma and normal squamous epithelium in esophagus?

Answer 1

• normal epithelium: orderly process of maturation from basal layer to outside getting pinker; well differentiated cells; no surface keratin; mitosis only in the basal and parabasal layers of cells
• in carcinoma: keratin pearls, more densely stained nuclei, mitosis can occur everywhere

Question 2

What is the “desmoplastic” reaction?

Answer 2

• desmoplasia = stromal response to tumor invasion; proliferation of fibroblasts around cancer cells

Question 3

2 features that distinguish a carcinoma as being squamous cell type?

Answer 3

1. extracellular keratin/keratin pearls

2. intercellular bridges

Question 4

Gross characteristics of squamous cell carcionma?

Answer 4

firm and tan or white
whiteness corresponds to quantity of keratin
tumor margins unencapsulated and usually infiltrative

Question 5

What is chronic gastritis?

Answer 5

presence of chronic mucosal inflammatory changes + inflammatory cells leading to mucosal atrophy and intestinal metaplasia

Question 6

How does chronic gastritis manifest on histology?

Answer 6

• gastric glands surrounded by lymphocytes, plasma cells, and sometimes eosinophils
• lymphoid follicles in basal mucosa

Question 7

Where does adenocarcinoma always begin from?

Answer 7

always begins from the mucosa

Question 8

What is structure of adenocarcinoma on histology?

Answer 8

• dilated glandular structures

- OR secretion of mucin, goblet cells

Question 9

How do you differentiate well-differentiated adenocarcinoma from normal gastric mucosal glands?

Answer 9

normal mucosa has ordered arrangement of identical vertically-oriented glands

tumor glands vary in size/shape; bigger nuclei; densely stained

Question 10

What determines early or advanced gastric carcinoma?

Answer 10

advanced = invasion deeper than submucosa

Question 11

What is histology of signet ring cell?

Answer 11

cell with intracellular accumulation of mucin

compresses nucleus to the side to form semilunar shape

Question 12

What kind of polarity are signet ring cells?

Answer 12

no polarity and no gland-like structures = very poorly differentiated

Question 13

What features of signet ring cell adenocarcinoma make it difficult to achieve a biopsy diagnosis?

Answer 13

• signet ring tumors do not form discrete mass

- can camouflage well with surrounding mucosal cells

Question 14

What 3 special stains to highlight adenocarcinoma tumor cells?

Answer 14

• PAS
• mucicarmine
• alcian blue

all stain for mucin

Question 15

What happens to gastric mucosa/submucosa in lymphoma?

Answer 15

• massively expanded so create giant rugal folds

Question 16

What is consistency of lymphoma?

Answer 16

• soft consistency = fish flesh because lack desmoplastic stroma

Question 17

How do you describe tumor border of lymphoma?

Answer 17

“pushing” [rather than infiltrative]

Question 18

How does lymphoma differ from adenocarcinoma grossly?

Answer 18

lymphomas soft, tan fleshy and lack desmoplastic stroma; borders well-demarcated rather than infiltrative

Question 19

What is MALT lymphoma?

Answer 19

mucosa associated lymphoid tissue = arises from mucosal B cells

Question 20

What organism linked to MALT lymphoma of the stomach?

Answer 20

H pylori –> if give antibiotics can get tumor regression

Question 21

How do carcinoid tumors appear on histology?

Answer 21

• solid tumor nests look like jigsaw puzzles
• lack glandular features
• nuclei round, uniform

Question 22

How do you distinguish carcinoid tumors from adenocarcinomas?

Answer 22

carcinoids = discrete sheets or small nests of tumor cells w/ rounded borders; each nest surrounded by fibrotic stromo; cells monotonous, round, unifomrly spaced, salt and pepper pattern of chromatin

adenocarcinomas: grow haphazardly, cells pleomorphic, nuclei vary in size and shape, lack speckling, more mitotic, glands/mucin

Question 23

What feature of nuclear chromatin is characteristic of neuroendocrine tumors?

Answer 23

nuclei have coarsely speckled salt and papper chromatin

Question 24

What stains to confirm diagnosis of carcinoid tumor?

Answer 24

silver stains [argyrophil or argentaffin] show cytoplasmic neuroendocrine granules of carcinoid as fine black dots

or use antibodies: chromogranin, synaptophyisn, neuron-specific enolase

Question 25

Why are carcinoid tumors firm?

Answer 25

desmoplastic reaction

Question 26

What do ulcers consist of?

Answer 26

- surface layer of necrotic debri and underlying exudate of fibrin/neutrophils - granulation tissue at based gradually replaced by scar tissue

Question 27

4 histo layers in a chronic peptic duodenal ulcer from top to bottom [lumen to base]?

Answer 27

1. necrotic debri 2. fibrinopurulent exudate 3. granulation tissue 4. fibrinous scar

Question 28

What are the constituents of granulation tissue?

Answer 28

highly vascularized loose fibroconnective tissue containing new capillaries w/ fibrocytes, myofibroblasts, histiocytes, inflammatory cells

Question 29

What histo change occurs in chronic duodenal ulcers that is not seen in gastric ulcers?

Answer 29

chronic duodenal ulcers often surrounded by hyperplastic brunner glands

Question 30

What is incidence of H pylori of stomach in patients with peptic ulcers of duodenum?

Answer 30

90% of duodenal ulcers accompanied by H pylori