Session 8 Lecture Notes

Question 1

What is the definition of a tumour?

Answer 1

Any detectable lump or swelling

Question 2

What are the two types of tumours?

Answer 2

Non-neoplastic eg an abscess

Neoplastic eg cancer is a malignant neoplasm

Question 3

What is the definition of metastasis?

Answer 3

A malignant neoplasm that has spread from its original site of origin (primary site) to a new site (secondary site)

Question 4

What is the definition of dysplasia?

Answer 4

A pre-neoplastic alteration in which cells show disordered tissue organisation
It is different to neoplasm because it IS REVERSIBLE

Question 5

What is the main difference between dysplasia and neoplasm?

Answer 5

Neoplastic cells are NOT reversible whereas the dysplasia cell changes ARE

Question 6

Are benign neoplasms cancerous?

Answer 6

NO only malignant neoplasms are cancerous

Question 7

What is the main difference between the activity of benign and malignant neoplasms?

Answer 7

Benign neoplasms are confined to their primary site of origin whereas malignant cells can metastasis to secondary sites

Question 8

What is the difference macroscopically between benign and malignant neoplasms?

Answer 8

Benign = have a pushing outer margin
Malignant = irregular outer margin and shape and may show necrosis and ulceration

Question 9

What is the difference microscopically between benign and malignant neoplasms?

Answer 9

Benign = cells are well differentiated ie they closely resemble the parent tissue
Malignant = cells range from well differentiated to poorly differentiated (anaplastic) ie they have no resemblance to target tissue

Question 10

As cells become more poorly differentiated what 4 changes are seen?

Answer 10

1. Increased nuclear size and nuclear to cytoplasmic ratio
2. Increased nuclear staining (hyperchromasia)
3. More mitotic figures
4. Increased variation in size and shape of cells and nuclei (pleomorphism)

Question 11

What is pleomorphism?

Answer 11

Cells that vary in size and shape as well as different nuclei appearances

Question 12

What is hyperchromasia?

Answer 12

Darkly stained nuclei

Question 13

Grade is used to indicate level of differentiation. Is a high grade well or poorly differentiated?

Answer 13

Low grade = well differentiated

High grade = poorly differentiated

Question 14

The modified bloom richardson grading for breast cancer looks at which 3 factors?

Answer 14

1. Tubules
2. Mitosis
3. Nuclear pleomorphism

Question 15

What does in situ mean?

Answer 15

The tumour is above the basement membrane

Question 16

Are the majority of mutations due to intrinsic or extrinsic factors?

Answer 16

Extrinsic factors (approximately 85%)

Question 17

What 2 things are needed to cause mutation?

Answer 17

1. Initiators (mutagenic agents)

2. Promotors (cause cell proliferation)

Question 18

What is lyonisation?

Answer 18

This is X linked inactivation
One of the copies of the X chromosome in females is randomly inactivated to prevent double the amount of gene products being produced in women than men

Question 19

Are neoplasms monoclonal and what does this mean?

Answer 19

Yes they are
They originate from a single founding cell
Initiator + Promotor + Progression = monoclonal cell population developing into a neoplasm

Question 20

What genes are altered during neoplasm formation?

Answer 20

1. Proto-oncogenes - they become abnormally activated to become oncogenes
2. Tumour suppressor genes - they become abnormally inactivated so can’t prevent neoplasm formation

Question 21

Are proto-oncogenes and tumour suppressor genes dominant or recessive alleles?

Answer 21

Proto-oncogenes = dominant
When one is activated (to become an oncogene) it drives proliferation
Tumour suppressor genes = recessive
Both have to be inactivated in order for them to stop functioning

Question 22

What 2 types of carcinoma are there?

Answer 22

1. In situ
2. Invasive
   In situ means the cancer has not penetrated the basement membrane whereas invasive it has

Question 23

What would you call a benign vs malignant neoplasm in the bladder epithelium?

Answer 23

Benign = transitional cell papilloma
Malignant = transitional cell carcinoma

Question 24

What would you call a benign vs malignant neoplasm in the glandular epithelium?

Answer 24

Benign = adenoma
Malignant = adenocarcinoma

Question 25

What is a basal cell carcinoma?

Answer 25

A malignant neoplasm in the skin epithelium

Question 26

Can lymphoid or haemopoeitic neoplasms be benign and malignant?

Answer 26

No - they are always considered malignant

Question 27

Are germ cell neoplasms benign or malignant? What are they called?

Answer 27

``` Germ cells are found in the testis and ovaries In the testes they are MALIGNANT In the ovaries they are BENIGN Testis = malignant teratoma Ovaries = benign teratoma ```

Question 28

What are blastomas?

Answer 28

Neoplasms that arise from immature precursor cells and mainly occur in children

Question 29

What are the 3 stages in which a malignant neoplasm gets from a primary to secondary site?

Answer 29

1. Grow and invade at primary site 2. Enter a transport system and lodge at secondary site 3. Grow at the secondary site to form a new tumour (colonisation)

Question 30

Invasion into surrounding tissues by carcinomas requires 3 stages, what are they?

Answer 30

1. Altered adhesion 2. Stromal proteolysis 3. Motility

Question 31

What are the 3 ways in which stromal cells can reach distant sites?

Answer 31

1. Travel through bloodstream 2. Travel through lymphatic vessels 3. Travel through fluid in body cavities (transcoelomic spread)

Question 32

What are micrometastasis?

Answer 32

Surviving microscopic deposits of metastasis that fail to grow

Question 33

What is tumour dormancy?

Answer 33

When a person harbours many micrometastases

Question 34

Malignant neoplasms that travel in lymph vessels are likely to metastasis where?

Answer 34

In the lymph nodes

Question 35

Malignant neoplasms that travel in the bloodstream are likely to metastasis where?

Answer 35

In the lung or liver as this is often the next capillary bed that they encounter However it depends upon the cancer niche

Question 36

What transport system do carcinomas vs sarcomas use when they metastasise?

Answer 36

``` Carcinomas = most often travel in the lymphatics Sarcomas = most often travel in the bloodstream (particularly liver, lungs, bone and brain) ```

Question 37

Which neoplasms most frequently spread to the bone?

Answer 37

Breast, lung, kidneys, thyroid and prostrate cancer

Question 38

What are paraneoplastic syndromes?

Answer 38

The indirect systemic effects of a neoplasm eg hormone secretion or increasing tumour burden

Question 39

What are the 4 main local effects of a neoplasm?

Answer 39

1. direct invasion and destruction of tissue 2. ulceration at the surface leading to bleeding 3. compression of adjacent structures 4. blocking tubes and orifices