Intestinal Neoplasia

Question 1

What are the 4 main types of cancer in the GI tract?

Answer 1

Adenocarcinoma
Lymphoma
Neuroendocrine/carcinoid tumour
Gastrointestinal stromal tumour (GIST)

Question 2

List 6 other, less common types of GI cancer.

Answer 2

Small cell carcinoma
Squamous cell carcinoma
Metastatic carcinoma
Adenosquamous carcinoma
Undifferentiated tumours
Mixed carcinoid-adenocarcinoma

Question 3

What types of benign cancer happens in the GI tract? (1)

Where do these originate from?

Answer 3

Adenoma (benign polyps)

Origin: glandular epithelium

Question 4

List a differential diagnosis for benign polyps in the GI tract. (4)

Answer 4

Hyperplastic/metaplastic glands
Hamartomatous polyps
Inflammatory polyps
Submucosal lesions, e.g.
-Lipoma
-Leiomyoma

Question 5

What are the features of low grade dysplasia in the GI tract? (3)

Answer 5

Slight disorganisation of mucosa (loss of normal “honeycomb” crypt pattern)
Larger crypt cells
Poorly developed cells

Question 6

What are the features of high grade dysplasia in the GI tract? (4)

Answer 6

Complex, poorly organised mucosa
Poorly developed cells
Cribriform pattern (multiple lumens in complex glands)
Enlarged nuclei

Question 7

What is the most common type of malignant GI tumour?

Answer 7

Adenocarcinoma

Question 8

List 7 risk factors for adenocarcinoma.

Answer 8

Age 50+ yo
Polyps larger than 10mm
Presence of existing adenomas/polyps (3+ large polyps, OR 5+ polyps of any size)
Inflammatory bowel disease
Family history
Other carcinomas
Polyposis syndromes (e.g. FAP, HNPCC)

Question 9

Describe the histology of a GI adenocarcinoma. (2)

Answer 9

High grade dysplasia

Invasion into muscularis propria

Question 10

What methods can you use to stage colorectal adenocarcinoma?

Answer 10

Duke’s staging

TNM staging

Question 11

Describe Duke’s staging for colorectal adenocarcinoma. (4)

Answer 11

A - cancer confined to mucosa and submucosa
B - cancer invading muscularis propria
C - cancer invading lymph nodes
D - distant metastases

Question 12

Describe the TNM staging system for colorectal adenocarcinoma. (3)

Answer 12

TUMOUR:
T1 - tumour confined to mucosa/submucosa
T2 - tumour invading muscularis propria
T3 - tumour invading pericolorectal tissues/lymph nodes
T4 - distant metastases 

NODES:
N0 - no nodes
N1 - 1-3 nodes
N2 - 4+ nodes

METASTASES:
M0 - no mets
M1 - distant mets

Question 13

Apart from having a late stage, list 3 other poor prognostic factors in colorectal adenocarcinoma.

Answer 13

Venous invasion
Perineural invasion
Involved margin (incomplete excision)

Question 14

Describe the histology of neuroendocrine/carcinoid tumours. (2)

Answer 14

Nests of cells

Positive immunocytochemistry staining

Question 15

Describe the classification of neuroendocrine/carcinoid tumours. (4)

Answer 15

Well differentiated, benign behaviour
Well differentiated, uncertain behaviour
Well differentiated, low grade malignant carcinoma
Poorly differentiated, high grade malignant carcinoma

Question 16

List 3 types of lymphoma found in the GI system. Which one is the most common?

Answer 16

Enteropathy associated T cell lymphoma (most common)
Hodgkin’s lymphoma
Non-Hodgkin’s lymphoma

Question 17

Describe the histology of gastrointestinal stromal tumours (GIST). (2)

Where do these tumours originate from?

Answer 17

Spindle shaped cells
Positive CD 117 stain

Origin: interstitial cells of Cajal

Question 18

List 2 genetic syndromes which can cause familial colon cancer.

Answer 18

FAP 
Lynch syndrome (HNPCC)

Question 19

Which genes are associated with HNPCC? (2)

Answer 19

MSH2

MLH1

Question 20

Which gene is associated with FAP?

Answer 20

APC

Question 21

Which types of cancer are associated with chronic inflammation in the GI tract? (2)

Answer 21

Adenocarcinoma

Enteropathy associated T cell lymphoma