Pathology of Gastrointestinal Cancers

Question 1

What is meant by an adenoma?

Answer 1

Benign neoplastic growth e.g a dysplastic polyp in the colon / rectum.

Question 2

What are the key differences between benign and malignant neoplasms?

Answer 2

Malignant neoplams are infiltrating and invasive to tissue and metastasise to other sites.

Benign neoplasms are localised and encapsulated.

Question 3

Metastisis

Answer 3

Secondary deposit of cancer away from the primary cancer.

Question 4

Dissemination (metastasis) occurs through what 4 processes?

Answer 4

1. Haematogenous spread - venous to liver/lungs.
2. Lymphatic spread to regional lymph nodes.
3. Seeding of body cavities e.g peritoneal cavity.
4. Mechanical spread e.g needle biopsy tract. (Iatrogenic).

Question 5

Which of well differentiated and poorly differentiated neoplasms have the worse prognosis?

Answer 5

Poorly differentiated malignant neoplasms have the worst prognosis.

Question 6

What microscopic features indicate malignancy?

Answer 6

1. Increased Nuclear:Cytoplasmic ratio as the nucleus enlarges.
2. Pleomorphism - lot’s of different forms.
3. Hyperchromatic (dark) nuclei
4. Mitoses
5. Loss of polarity - no clear organisation

Question 7

Carcinoma refers to cancer of the

Answer 7

epithelium

Question 8

Melanoma refers to cancer of the

Answer 8

Melanocytes

Question 9

Sarcoma refers to cancer of the

Answer 9

Mesenchymal cells / germ cell tumour

Question 10

What is the normal epithelial lining of the oesophagus?

Answer 10

Squamous epithelium

Question 11

What type of cancer normally forms in the oesophagus? (excluding barretts)

Answer 11

Squamous cell carcinoma

Question 12

What changes to epithelium occur in Barrett’s oesophagus?

Answer 12

Squamous epithelium is replaced by glandular epithelium (columnar metaplasia).

Risk of malignancy - formation of an adenocarcinoma.

Question 13

Why does metaplasia of squamous to columnar epithelium occur in Barrett’s oesophagus?

Answer 13

The squamous epithelium is unable to deal with the acidic conditions resulting from GORD, where as the columnar epithelium can - hence you get metaplasia to columnar epithelium.

Question 14

Staging of oesophageal dyplasia

Answer 14

Question 15

What epithelium lines the stomach?

Answer 15

Simple columnar - glandular epithelium

Question 16

What are the risk factors of gastric cancer?

Answer 16

Smoking

Diet

H.pylori infection

Question 17

What type of malignancy may be seen in the stomach?

Answer 17

Adenocarcinoma

Question 18

Metaplasia dysplasia carcinoma sequence

Answer 18

Question 19

What are the two main types of gastric adenocarcinoma?

• what’s the prognosis for each?

Answer 19

Intestinal type - low grade, localised growth

Diffuse type - infiltrative - consists of poorly cohesive maligant cells that are invasive.

Signet ring cell carcinoma = diffuse type

Question 20

Signet ring cell carcinoma

Answer 20

Signet ring cell carcinoma (SRCC) is a rare form of highly malignant adenocarcinoma that produces mucin.

Question 21

Histology of gastric adenocarcinoma

Answer 21

Question 22

Histology of signet ring cell carcinoma

Answer 22

Question 23

What are the different types of gastric tumours?

Answer 23

Gastric adenocarcinoma

Neuroendocrine tumours

Gastrointestinal stromal tumours

Lymphoma B-cell tumours

Question 24

H.pylori can give you what two types of stomach cancer?

Answer 24

Gastric adenocarcinoma

Lymphoma

Question 25

What do gastric neuroendocrine tumours secrete?

Answer 25

Gastric neuroendocrine tumours secrete gastrin.

Question 26

What is the histology seen here?

Answer 26

Question 27

What cause gastric neuroendocrine tumours to form?

Answer 27

Arise in stomach on a background of hypergastrinaemia (atrophic gastritis or gastrin-producing neoplasm) or occur sporadically. Gastrinoma – duodenum or pancreas.

Question 28

Summary of gastrointestinal stromal tumours.

Answer 28

Question 29

What can been seen here?

Answer 29

Question 30

What is the most common cause of small bowel tumours?

Answer 30

Metastasis

Question 31

What are the different types of small bowel tumours?

Answer 31

* Neuroendocrine tumours most common neoplasm. * GISTs * Lymphoma * Small bowel adenocarcinoma

Question 32

What are the risk factors of small bowel adenocarcinoma?

Answer 32

Familial Adenomatous Polyposis (FAP), Crohn’s disease, coeliac disease.

Question 33

What is the most common type of tumour seen in the appendix?

Answer 33

Neuroendocrine tumour

Question 34

How is the risk of progression of an adenoma in the colon classified?

Answer 34

Risk of progression to invasive adenocarcinoma is related to the number, size, villous architecture, and grade of dysplasia. Note: average progression from adenoma to adenocarcinoma is around 10 years.

Question 35

Histology of colorectal adenoma's Tubular Villous Low grade High grade

Answer 35

Question 36

What is being shown here in this histology slide?

Answer 36

Question 37

Name the condition shown? What is the treatment?

Answer 37

Familial Adenomatous Polyposis Treatment is Colectomy

Question 38

How are tumour staged?

Answer 38

TNM Classification T - extent of primary tumour N - lymph node involvement M - Distant metastases

Question 39

Tumour Staging (T)

Answer 39

Question 40

Lymph Node Staging (N)

Answer 40

Question 41

Metastasis staging (M)

Answer 41

Question 42

What can be seen in this histology?

Answer 42

Question 43

What can be seen in this histology?

Answer 43

Question 44

Peutz Jeghers Syndrome

Answer 44

Peutz-Jeghers syndrome is characterized by the development of noncancerous growths called hamartomatous polyps in the gastrointestinal tract (particularly the stomach and intestines) and a greatly increased risk of developing certain types of cancer.

Question 45

What does lynch syndrome lead to?

Answer 45

Lynch syndrome which is characterised by aggressive right sided colonic malignancy and endometrial cancer is caused by microsatellite instability of DNA repair genes.