Lecture 40 - Behaviour of tumours

Question 1

How many new cases of cancers occur every year in the UK?

Answer 1

350,000

Question 2

True or false: Cancer causes more than 1 in 4 deaths in the UK

Answer 2

True

Question 3

How do malignant tumours behave?

Answer 3

1. Invasion
2. Metastasis
3. Angiogenesis

Question 4

What is invasion of malignant tissue?

Answer 4

Invades adjacent normal tissue
Destroys normal tissue

Question 5

What is metastasis of malignant tissue?

Answer 5

Spreads from site of origin to a distant site establishes a new tumour there

Question 6

What is the name of the mechanisms used my cancerous cells allowing them to become more mobile and free moving?

Answer 6

epithelial-mesenchymal transition

Question 7

what is require for a tumour to metastasise?

Answer 7

Invasion

Question 8

Describe the typical arrangement of epithelial cells:

Answer 8

tightly connected, polarised and tethered to one another

Question 9

Describe the typical arrangement of mesenchymal cells:

Answer 9

loosely connected (meaning they are able to migrate)

Question 10

What are the two stages of the epithelial-mesenchymal transition?

Answer 10

1) reducing adhesion

2) producing proteolytic enzymes

3) Increased motility

4) Mechanical pressure

Question 11

How does cancer spread using epithelial - mesenchymal transition?

Answer 11

In cancer, epithelial cells gain mesenchymal properties and can invade and migrate

Question 12

Give an example of a cell-to-cell adhesion molecule:

Answer 12

cadherins
A mutation in E-cadherin in the tumour  reduced cell-cell adhesion.

Question 13

Give an example of a cell to matrix adhesion molecule:

Answer 13

integrin
Changes in integrin expression leads to decreased cell-matrix adhesion

Question 14

What is the most important proteolytic enzyme in neoplastic invasion?

Answer 14

Matrix metalloproteinases

Question 15

What cells secrete matrix metalloproteinases?

Answer 15

malignant neoplastic cells

Question 16

Give three examples of matrix metalloproteinases:

Answer 16

1) interstitial collagenases

2) gelatinases

3) stromelysins

Question 17

What proteins does interstitial collagenase break down?

Answer 17

type I, II and III collagen

Question 18

What proteins does gelatinase break down?

Answer 18

type IV collagen and gelatine

Question 19

What proteins does stromelysin break down?

Answer 19

type IV collagen and proteoglycans

Question 20

Describe the balance between matrix metalloproteinases and tissue inhibitors of metalloproteinases in cancer?

Answer 20

the tissue favours extracellular matrix breakdown

Question 21

What path do malignant neoplasms invade along?

Answer 21

the path of least resistance

Question 22

Give two examples of ‘paths of least resistance’ used my malignant neoplasms when invading?

Answer 22

1) blood vessels

2) nerves

Question 23

What is metastasis?

Answer 23

where a tumour spreads from the site of origin (primary) to a distant site to establish a tumour there (secondary)

Question 24

True or false: the tumour mass of the secondary tumour exceeds that of the primary lesion

Answer 24

true

Question 25

What two things are extremely resistance to neoplastic invasion?

Answer 25

1) Cartilage 2) Bone

Question 26

Give three easily identifiable clinical presentations of metastasis:

Answer 26

1) palpable lymph nodes 2) ascites 3) bone lesions

Question 27

What is the first step in the metastatic sequence?

Answer 27

detachment invasion

Question 28

What is detatchement invasion?

Answer 28

where cells of a primary tumour break away

Question 29

What is the name given to the process of malignant tumour cells entering blood vessels?

Answer 29

intravasation

Question 30

Give an example of a method used by tumour cells to evade the host immune system when travelling in the blood:

Answer 30

tumour cells remove their MHC I expression to reduce detection

Question 31

What is the name of the process whereby tumour cells anchor to the wall of the endothelium and exit blood vessels?

Answer 31

adherence extravasation

Question 32

Give the four main routes of metastasis:

Answer 32

1) lymphatics 2) haematogenous 3) transcoelomic 4) implantation

Question 33

Where do secondary tumours from when cancers spread through lymphatics?

Answer 33

lymph nodes

Question 34

What is the most common route of metastasis used by carcinomas?

Answer 34

lymphatic route

Question 35

What is the most common route of metastasis used by sarcomas?

Answer 35

haematogenous route

Question 36

What organs are common sites of secondary tumours when cancers spread through the blood? (4)

Answer 36

1) liver 2) lungs 3) bone 4) brain

Question 37

Where do bone metastases most frequently come from?

Answer 37

1) Lung 2) Breast 3) Kidney 4) Thyroid 5) Prostate

Question 38

What is the transcoelomic route of metastasis?

Answer 38

spread across the peritoneum or pleural cavity leading to an effusion containing neoplastic cells

Question 39

What is the implantation route of metastasis?

Answer 39

the spillage of tumour cells in surgery

Question 40

Fill in the gap: tumours cannot grow more than _-_mm without a blood supply

Answer 40

2-3mm

Question 41

What is angiogenesis?

Answer 41

Growth of blood vessels on existing vasculature Normal part of growth and healing

Question 42

What molecule do tumour cells express to promote the sprouting of new vessels?

Answer 42

vascular endothelial growth factor (VEGF)

Question 43

What is meant by 'stage' in relation to cancer?

Answer 43

the extent of tumour spread/ how far along the tumour is (has it metastasised?)

Question 44

What is meant by 'grade' in relation to cancer?

Answer 44

the extent of aggressiveness of a tumour/ how quickly it is progressing

Question 45

What system is used to assess the stage of a cancer?

Answer 45

The TNM staging system

Question 46

What does TNM stand for?

Answer 46

tumor-node-metastasis

Question 47

What does the TNM scale assess?

Answer 47

the extent of tumour and nodal spread and metastasis

Question 48

What staging system is used for colorectal cancer?

Answer 48

Dukes staging system

Question 49

What is meant by the A-D scale used in Dukes staging system for colorectal cancer?

Answer 49

A- no invasion through the bowel wall D- distant metastasis

Question 50

What staging system is used for lymphomas?

Answer 50

Ann Arbor system

Question 51

What is stage 1 Lymphoma?

Answer 51

Lymphoma in one group of lymph nodes

Question 52

What is stage 2 Lymphoma?

Answer 52

Lymphoma in 2 or more groups of lymph nodes

Question 53

What is stage 3 Lymphoma?

Answer 53

Lymphoma both sides of diaphragm

Question 54

What is stage 4 Lymphoma?

Answer 54

Lymphoma in organ not part of lymphatics / lymphoma in bone marrow, liver or lung

Question 55

What are the two grades of cancer?

Answer 55

low and high grade

Question 56

What things do we consider when we are determine the grade of the cancer?

Answer 56

1. How much do the cancer cells resemble the normal tissue = differentiation 2. The variation in size and shape of the cancer cells = pleomorphism 3. How many cells are actively dividing, can count mitotic figures = proliferation

Question 57

How does well differentiated tumours present?

Answer 57

Cells closely resemble those of normal tissue = low grade

Question 58

How does a poorly differentiated tumour differentiated?

Answer 58

Cells hardly resemble those of normal tissue = high grade

Question 59

Does mitoses only indicated malignancy?

Answer 59

mitoses can be seen in normal tissue  do not indicate malignancy

Question 60

What type of mitotic figures are seen during malignancy?

Answer 60

Tripolar Quadripolar Multipolar spindles