Stomach: other gastric tumours

Question 1

What percentage of gastric tumors does gastric lymphoma represent?

Answer 1

5%

Gastric lymphoma is considered a rare type of gastric tumor.

Question 2

What is the male-to-female ratio for gastric lymphoma?

Answer 2

2:1

Question 3

What is the median age range for patients with gastric lymphoma?

Answer 3

60-65

Patients with HIV tend to present older than this.

Question 4

What are common presenting symptoms of gastric lymphoma?

Answer 4

Dyspepsia and upper abdominal discomfort

Often presents similarly to peptic ulceration.

Question 5

What is the primary method for investigating gastric lymphoma?

Answer 5

Endoscopy

Question 6

What imaging techniques are used for staging gastric lymphoma?

Answer 6

EUS, CT chest/abdomen/pelvis, and bone marrow biopsy

Question 7

Which staging system is used for gastric lymphoma?

Answer 7

Modified Blackeledge system

Question 8

What characterizes Stage 1 gastric lymphoma?

Answer 8

Confined to GI tract without serosal penetration, single primary or multiple non-contiguous lesions

Question 9

What does Stage 2 gastric lymphoma indicate?

Answer 9

Extends into abdominal nodes from primary

Includes II1 (local nodes) and II2 (distant nodes).

Question 10

What is the definition of Stage 3 gastric lymphoma?

Answer 10

Perforation of serosa with involvement of other structures

Question 11

What does Stage 4 gastric lymphoma refer to?

Answer 11

Disseminated extranodal disease

Question 12

What is MALT in the context of gastric lymphoma?

Answer 12

Mucosa associated lymphoid tissue

Question 13

What is associated with low-grade MALT lymphoma?

Answer 13

H. pylori

May regress spontaneously with treatment of H. pylori.

Question 14

What is the recommended surveillance for low-grade MALT lymphoma?

Answer 14

6 monthly biopsy for 2 years

Question 15

What treatment is indicated for high-grade or persistent MALT lymphoma?

Answer 15

Chlorambucil and rituximab

Question 16

What treatment is given if there is large cell transformation in MALT lymphoma?

Answer 16

CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone) and rituximab

Question 17

What did the RCT show regarding CHOP treatment?

Answer 17

CHOP alone gave the best survival rates compared to CHOP + surgery

Question 18

In what setting is surgery for gastric lymphoma limited to?

Answer 18

Emergency setting

Question 19

What does GEP-NETs stand for?

Answer 19

Neuroendocrine gastroenteropancreatic tumors

Question 20

What is MALT?

Answer 20

Mucosa-associated lymphoid tissue (MALT) is scattered along mucosal linings to protect the body from an enormous quantity and variety of antigens.

Examples of MALT include the tonsils, Payer patches within the small intestine, and the vermiform appendix.

Question 21

What are the types of MALT?

Answer 21

MALT includes:
* Gut-associated lymphoid tissue (GALT)
* Bronchial/tracheal-associated lymphoid tissue (BALT)
* Nose-associated lymphoid tissue (NALT)
* Vulvovaginal-associated lymphoid tissue (VALT)

These types are associated with different mucosal linings in the body.

Question 22

What is MALToma?

Answer 22

MALToma is a B cell lymphoma arising from the MALT. It is the most common primary GI lymphoma worldwide.

NHL accounts for 2-3% of all malignancies, and MALTomas comprise approximately 5% of all NHLs.

Question 23

What are the predominant sites of MALT-lymphoma?

Answer 23

Predominant sites include:
* Stomach (75%)
* Small bowel (9%)
* Ileocaecal (7%)
* Multifocal (6%)
* Rectum (2%)
* Colon (1%)
* Lung
* Salivary Glands
* Ocular adnexa
* Skin

The stomach is the most commonly affected site.

Question 24

Why is MALToma considered a malignant condition?

Answer 24

MALToma is considered malignant due to:
* Monoclonality
* Non-random chromosomal aberration
* Histologic transformation to high-grade lymphoma
* Metastasis to lymph nodes/bone marrow

These characteristics distinguish it from benign conditions.

Question 25

What is the pathogenesis of gastric MALToma?

Answer 25

The pathogenesis involves: * H. Pylori infection * Increase in MALT tissue * Additional genetic mutations * Malt lymphoma ## Footnote H. Pylori infection has been definitively established as a cause of MALTomas, with 90% of MALToma patients infected.

Question 26

What are the clinical features of gastric MALToma?

Answer 26

Clinical features include: * Median age 63 years * Equal gender distribution * Symptoms: epigastric pain, dyspepsia, nausea, vomiting, gastric bleeding * Duration of symptoms ranges from a few days to six years ## Footnote B symptoms can also occur.

Question 27

How is MALToma diagnosed?

Answer 27

MALToma is usually diagnosed at endoscopy with findings of: * Erythema * Erosions or ulcers * Most common site is antrum (41%) or multifocal (33%) ## Footnote A mass lesion on OGD is unusual.

Question 28

What are the staging investigations for gastric MALToma?

Answer 28

Staging investigations include: * Baseline bloods (LDH, B2 microglobulin) * OGD with multiple biopsies * CT Chest/Abdomen/pelvis * Bone marrow biopsy * EUS for evaluation of depth of invasion ## Footnote All diagnostic studies should be done regardless of the presentation site.

Question 29

What is the best staging system for MALToma?

Answer 29

The best staging system is still controversial, with options including: * Modified Blackledge staging system * TNM (when EUS is available) * Ann Arbor ## Footnote The Modified Blackledge system is recommended by an International workshop held in Lugano, Switzerland.