L18 - Anatomy & Cancer

Question 1

Define desmoplasia.

Answer 1

A growth of excessive supporting stroma surrounding a tumour

Question 2

Define anaplasia.

What are the characteristics of anaplastic tumours?

Answer 2

• Anaplasia is a condition of cells with poor differentiation

1 - Hyperchromatic nuclei

2 - Abundant mitosis

3 - Loss of polarity

4 - Presence of tumour giant cells

5 - Ischaemic necrosis

6 - Pleomorphism

Question 3

Define tumour giant cell.

Answer 3

A cell in which mitosis occurs so rapidly that multiple nuclei can be found within one cell, and there is an excessively large volume of cytoplasm (as the cell has reproduced nuclei faster than it has been able to split)

Question 4

Why might malignant tumours undergo ischaemic necrosis?

Answer 4

Malignant tumours might undergo ischaemic necrosis as the cancer cells are dividing faster than the blood supply is able to catch up

Question 5

Define pleomorphism.

Answer 5

• Pleomorphism is high variation in the size and shape of the cells and nuclei within a population of cancer cells
• This is characteristic of malignant tumours

Question 6

Define dysplasia.

Answer 6

Dysplasia is loss of cellular uniformity, which is reversible if the inciting stimulus is removed

Question 7

How does growth rate of a tumour affect differentiation?

Answer 7

-Growth rate inversely correlates with the level of differentiation

Question 8

List 3 mechanisms of cancer spread.

Answer 8

1 - Local spread (invading into surrounding structures)

2 - Lymphatic spread (via lymph vessels / nodes)

3 - Haematogenous spread (via venous drainage)

Question 9

What is a sentinel lymph node?

Why is it important clinically?

Answer 9

• A sentinel lymph node is the first lymph node that drains a tumour
• It is used to predict the likelihood of tumour spread (staging). If no cancer cells are found within it, unnecessary lymph node removal can be avoided
• The sentinel lymph node can also be removed to prevent lymphatic spread

Question 10

How is the sentinel lymph node of a tumour identified?

Answer 10

Identify by blue dye or radioactive tracer

Question 11

Where do GIT tumours commonly metastasise to?

Why?

Answer 11

• GIT tumours commonly metastasise to the liver

- This is because the GIT is drained by the hepatic portal vein, therefore metastasis can occur via haematogenous spread

Question 12

Which cancers metastasise to the lungs?

Answer 12

Structures drained by the systemic venous system