14 Neoplasia 2

Question 1

What causes an increased ‘tumour burden’?

Answer 1

Malignant cells spreading to and invading distant sites–> parasitic malignant cells

Question 2

What steps must a malignant cell go through to get from a primary site to a secondary site?

Answer 2

1- INVASION-Grow and invade @ primary site

2-TRANSPORT- Enter transport system and lodge @secondary site

3-COLONISATION- grow at secondary site- form new tumour (must evade destruction by immune cells at all points)

Question 3

What are the 3 alterations to a cell required for invasion to occur (i.e. create carcinoma cell phenotype?

Answer 3

Altered:

1. Adhesion-reduce E-cadherin expression and changed Integrin expression
2. Proteolysis- altered expression of MMPs (proteases)- degrade basement membrane
3. Motility- change Actin and Cytoskeleton (Process= EMT- Epithelial-to-Mesenchymal Transition)

Question 4

What do malignant cells form with nearby non-neoplastic cells when they take advantage of their growth factors and proteases?

Answer 4

Cancer niche

Question 5

What are the 3 TRANSPORT routes for malignant cells (to reach distant sites)?

Answer 5

1) Blood vessels (capillaries and venues)
2) Lymphatic vessels
3) Transcoelomic spread =Fluid in body cavities e.g. pleura, peritoneal, pericardial etc)

Question 6

Of the 3 steps required for metastasis of a neoplasm, which step is considered to greatest barrier?

Answer 6

3-COLONISATION

Question 7

What is are micrometastases?

Answer 7

Surviving microscopic deposits that fail to grow

Question 8

What is ‘tumour dormancy’?

Answer 8

An apparently disease free person- harbouring many metastases- malignant neoplasm can relapse

Question 9

What determines the site of a secondary tumour?

Answer 9

1. REGIONAL DRAINAGE OF BLOOD/LYMPH/COELOMIC FLUID- e.g. lymph node/next capillary bed
2. SEED AND SOIL- explains unpredictable distribution of blood-borne metastases due to interactions between malignant cell and niche at secondary site

Question 10

By which transport system do carcinomas tend to spread first?

Answer 10

Lymphatics- lymph nodes then blood-borne distant site

Question 11

By which transport system do sarcomas tend to spread?

Answer 11

Blood stream

Question 12

What are some common distant sites for blood-borne metastases?

Answer 12

Lung, bone, liver, brain

Question 13

Which neoplasms most commonly spread to bone?

Answer 13

Breast, bronchus, kidney, thyroid, prostate

Question 14

Give an example of a neoplasm that is aggressive and metastasises very early in its course.

Answer 14

Small cell bronchial carcinoma

Question 15

Give an example of a tumour that almost never metastasises.

Answer 15

Basal cell carcinoma of the skin

Question 16

How do we classify the effects that neoplasms have on their host?

Answer 16

Local

• Primary (neoplasm)
• Secondary (neoplasm)

Systemic

• Burden (tumour)
• Hormones (secreted by some neoplasms)
• Micellaneous

Question 17

What are ‘Paraneoplastic syndromes’?

Answer 17

Rare disorders triggered by autoimmune response to neoplasms.

Question 18

What are the local systemic effects of neoplasms due to? (4)

Answer 18

1. Direct invasion and destruction- of normal tissue
2. Ulceration at surface–> bleeding
3. Compression- adjacent structures
4. Blocking of tubes/orifices

Question 19

What effect does increasing the tumour burden have on the host?

Answer 19

Factors (eg. Cytokines) secreted:

• Cachexia- reduced appetite and weight loss
• Malaise (feeling ill)
• Immunosuppression
• Thrombosis

Question 20

Give examples of miscellaneous effects of neoplasms.

Answer 20

• Neuropathies affecting brain and peripheral nerves
• Skin problems e.g. pruritus (severe itching)
• Abnormal pigmentation
• Fever
• Finger clubbing
• Myositis (muscle inflammation)