GI Section 1: Luminal (Gastric Tumors)

Question 1

This is the most common mesenchymal tumor of the GI tract

Answer 1

GIST (Gastrointestinal Stromal Tumor)

(70% in stomach, duodenum is second most common — colon is actually the least common)

These can be benign or malignant

Question 2

What favors a benign GIST over a malignant GIST?

Answer 2

Lymph node enlargement is NOT a classic feature

Absence o fperigastric lymphadenopathyfavors a benign GIST over a malignant GIST or Gastric Adenocarcinoma

Question 3

Malignant GIST features

Answer 3

> 5 cm with ulceration - possible perforation

Question 4

Where to GIST mets?

Answer 4

Liver

Question 5

GIST is associated with what conditions?

Answer 5

Carney’s triad and NF-1

Carneys Triad (“Carney’s Eat Garbage”)

Chondroma (pulmonary)
Extra adrenal Pheochomocytoma
GIST

Question 6

Gastric CA is either?

Answer 6

A lymphoma (<5%)

or

AdenoCA (95%)

Rarely a malignant GIST

Question 7

Old (median, rare before 40)
+ Hx of H.Pylori

Answer 7

Gastric AdenoCA

Question 8

Gastric AdenoCA

Answer 8

Can obstruct (if it involves the antrum)

Question 9

Gastric AdenoCA mets to ovary =

Answer 9

Krukenberg Tumor

Question 10

Remnant of Gastroenterostomy in Gastric adenoCA?

Answer 10

“stump CA”

Question 11

Risks of Gastric AdenoCA

Answer 11

Pernicious anemia
Menetrier’s disease (giant mucosal folds in the proximal part of the stomach, diminished acid secretion, and a protein-losing state with hypoalbuminemia.)

Question 12

Swollen left supraclaviculare node =

Answer 12

Virchow node

Question 13

smoothly marginated and exophytic

Answer 13

GIST

Question 14

a large, ulcerated, heterogenous mass.

Answer 14

Gastric Adeno CA

Question 15

Describe the mass iin adenoCA?

Answer 15

The “mass” is often asymmetric wall thickening - focal and nodular - more than
12mm.

Question 16

Types of Gastric Lymphoma

Answer 16

Primary - MALT (mucosa-assisted lymphoid tissue)

or

Secondary (Systemic Lymphoma)

Question 17

Most common Extranodal site for NHL

Answer 17

The stomach

Question 18

H.pylori is a risk factor for these diseases

Answer 18

AdenoCA and Lymphoma

Question 19

Rarely causes gastric outlet obstruction, even when extensive

Answer 19

Gastric Lymphoma

Question 20

“crossing the pylorus ”

Answer 20

Gastric lymphoma

Question 21

Answer 21

Lymphoma - crossing the pylorus

Classic Look =
Diffiise wall thickening (>1 cm) * Without gastric outlet obstruction

Question 22

What can happen to Gastric lymphoma after chemo?

Answer 22

Can rupture

Question 23

Gastric Cancer is “More Likely” Than Lymphoma to…

Answer 23

More Likely to:
- Cause Gastric Outlet Obstruction
- to be in the distal stomach
- to extend beyond the serosa and obliterate adjacent fat plains
- to be a focal mass (95% of primary gastric tumors are adenocarcinoma)

Question 24

Although very rare, mets to the stomach is most commonly caused by this culprit, then the following

Answer 24

Melanoma

then breast (most classic) and lung

Question 25

multiple button type soft tissue nodules

Answer 25

Metastatic Melanoma

Question 26

Answer 26

Linitis plastica - can also be a look for lymphoma

diffuse infiltration and a contracted desmoplastic deformity resembling a stiff leather bottle.

Caused by metastatic breast (lobular CA) and lung CA