Angiogenesis and metastases

Question 1

Benign tumours

Answer 1

• Non-cancerous
• Capsulated - ring of fibrous capsule that prevents tumour from invading tissue
• Non-invasive
• Slow growing
• No metastases
• Smooth and mobile

Question 2

Malignant tumours

Answer 2

Non-capsulated, fast growing tumours, craggy, cancerous

Question 3

What is transcoelomic spread?

Answer 3

Spread via cavities e.g. peritoneal, pericardial or joint

Question 4

What is lymphatic spread?

Answer 4

Spread through lymphatic vessels , follows natural route of lymphatic drainage
Biopsy the sentinel node to test

Question 5

What is haematogenous spread?

Answer 5

Primary tumour penetrates into blood vessels and passively transported to distant sites

Question 6

Is arterial or venous penetration more common and why ?

Answer 6

Venous - walls are thinner

Question 7

What is perineurial spread?

Answer 7

Along a nerve

Question 8

Where does lung cancer metastasise to ?

Answer 8

Adrenal glands, brain and bone

Question 9

Where does breast cancer metastases to ?

Answer 9

Bone, liver, lung and brain

Question 10

Where does colon cancer metastasise to ?

Answer 10

Liver

Question 11

Where does pancreatic cancer metastise to ?

Answer 11

Liver and lungs

Question 12

Where does melanoma metastise to ?

Answer 12

Brain

Question 13

Where does ovarian cancer spread to ?

Answer 13

Pleural cavity and liver

Question 14

How does cancer invade the ECM?

Answer 14

• Carcinoma breaches basement membrane and interstitial connective tissue → enters circulation
• ‘Loosening up’ of tumour cell-cell interactions: normal cells glued together and to ECM by E-cadherins. In epithelial tumours )colon, stomach, breast), E-cadherin function is lost which allows cells to detach and invade tissues
• Degradation of ECM: tumour cells make proteolytic enzymes e.g. MMPs, cathepsin D and urokinase plasminogen activator. This remodels components of BM and cleaves collagen fibres
• Attachment to ECM components: cleavage of collagen 4 by MMP9 and MMP2 generates novel sites that bind to receptors on tumours and stimulates migration
• Migration and invasion: tumour cells propelled by many factors

Question 15

TNM grading system

Answer 15

T1 = 0-2cm
T2 = 2-5cm
T3 = >5cm
T4 = tumour broken through skin or attached to chest wall

N0 = no LNs
N1 = swollen LNs
N2 = swollen and lumpy LNs
N3 = LNs near collarbone 

M0: tested LNs are cancer free
M1: tested LNs show cancer cells

N0: no palpable LNs
N1: some swollen LNs
N2: lumpy and swollen LNs
N3: LNs near collarbone

Question 16

Angiogenesis and cancer

Answer 16

Tumours need nutrients and o2 etc for survival

New vessels are leaky so promote metastases