Neoplasia

Question 1

Define tumour

Answer 1

A swelling- any clinical detectable lump or swelling

Question 2

Define neoplasm

Answer 2

An abnormal growth of cells that persists after the initial stimulus is removed.

Question 3

Define oncology

Answer 3

Study of tumours and neoplasms

Question 4

Define benign neoplasms

Answer 4

Gross and microscopic appearances are considered to be innocent , implying that it will remain localised and will not spread to other sites

Question 5

Define cancer

Answer 5

A malignant neoplasm

Question 6

Define malignant neoplasm

Answer 6

An abnormal growth of cells that persists after the initial stimulus has been removed and invaded surrounding tissue with the potential spread to distant sites

Question 7

Define metastasis

Answer 7

Malignant neoplasm that has spread from its original site to a new non-contiguous site

Question 8

What is dysplasia?

Answer 8

Pre-neoplasticism alteration in which cells show disordered tissue organisations.This is reversible.Cells in dysplasia can look malignant but they have not yet invaded. They exhibit considerable pleomorphism , with large hyperchromatic nuclei and high nuceleur to cytoplasmic ratios.

• Precursor to malignancy

This leads to carcinoma in situ where epithelial cells exhibit the same features as malignant cells ( the cells have not yet invaded the basement membrane). Therefore cells are NOT yet malignant.

Question 9

What are the two branches of tumours ?

Answer 9

Non neoplastic ( eg abscess , haematoma)

Neoplastic ( can either be benign or malignant ( cancer ) . If it is malignant you need to consider whether it is primary or secondary ( metastasis)

Question 10

Is neoplasia reversible ?

Answer 10

No it is irreversible

Question 11

What is the difference between primary and secondary malignant neoplasm ?

Answer 11

Primary = the original location of the malignant neoplasm is the primary site

Secondary = the place to which it has spread is the secondary site

Question 12

How can we tell the difference between a benign tumour and malignant tumour ?

Answer 12

1. The behaviour of each tumour : benign neoplasms remain confined to their site of origin and do not produce metastases. Whereas malignant neoplasms invade and have the potential to metastasise. Also , as they grow in a confined local area they have a pushing outer margin. Whereas in malignant tumours they have an irregular outer margin and shape. They do not form a pseudo capsule the same way benign tumour does. Benign tumours grow slower than malignant tumours.
2. Differences in appearances to the naked eye /microscope : benign tumours resembles tissues of origin , few mitosis m normal or mild increase in nuclear to cytoplasmic ratio. Cells are uniform throughout the tumour. Malignant tumours are the opposite.
3. Differentiation : malignant tumours are poorly differentiation whereas benign tumours are well differentiated

Question 13

Define differentiation

Answer 13

The process of becoming different by growth or development

Question 14

Do benign neoplasms closely resemble their parents tissue or not ? What about malignant neoplasms ?

Answer 14

They closely resemble the parent tissue - considered to be well differentiated

Malignant neoplasms range from well to poor differentiated , dependant on how closely they resemble the cell of origin

Question 15

What does anaplastic mean ?

Answer 15

Cells with no resemblance to any tissue

Question 16

With worsening differentiation ( become more malignant ) how do the individual cells change ?

Answer 16

1. Increase nuclear size
2. Increased nuclear to cytoplasmic size
3. Increased nuclear staining - become darker ( hyperchromasia )
4. Increased mitotic figures
5. Abnormal mitotic figures ( Mercedes Benz Sign )
6. Variation in size and shape of cells and nuclei (pleomorphism )

Question 17

What is a another term for a poorly differentiated tumour ?

Answer 17

A high grade tumour

Grade 1 to grade 3 ( gets worser )

Question 18

Why do we get neoplasia ?

Answer 18

1. Non-lethal genetic damage : genetic damage that can go unchecked by the cell cycle , by the immune system that can then proliferate.

A tumour is formed by the clonal expansion of the single precursor cells that has incurred genetic damage.

Genetic damage is caused by mutations which are caused by initiators called mutagenic agents

Question 19

Give examples of mutagenic agents (initiators of mutations )

Answer 19

Chemicals : smoking , alcohol consumption , diet and obesity

Infectious agents : HPV

Radiation :

Inherited mutations eg BRACA1 BRACA2

Question 20

Outline the general process by which a neoplasm forms

Answer 20

1. You have a cell population which is stimulated by an initiator that causes a mutation.
2. This cell then undergoes cell proliferation by promotors
3. This continues to proliferate which causes a monoclonal collection of cells.
4. The neoplasm then emerges from this monoclonal group of cells from a process called progression - this is characterised by the accusation of yet more mutations.

Question 21

Which genes are affected by mutations ?

Answer 21

There are four classes of normal regulatory genes :

1. Growth promoting proto-oncogenes : mutations that activate these generally cause an excessive increase in one or more normal functions. Once mutated they are now called ‘oncogenes ‘ which have the ability to promote cell growth in the absence of normal growth promoting cell signals. They are dominant over their normal counterparts ( only one gene needs to be mutated to have an effect )
2. Growth inhibiting tumour suppressor genes : their normal function is to stop cell proliferation. A mutation in this causes a loss of function. Usually , both allles must be damaged for transformation to occur. Leads to failure of growth inhibition.
3. Genes that regulate programmed cell death : enhances survival of cells

4, genes involved in DNA repair : impair the ability of the cell to recognise and repair non lethal genetic damage in other genes

Question 22

NAMING NEOPLASMS : what do benign and malignant tumours end in ?

Answer 22

Benign tumours : end in ‘oma’

Malignant tumours : if epithelial (90% of the case )end in ‘ carcinoma ‘. And if Stromal they end in ‘ sarcoma ‘

Question 23

If there is a benign epithelial neoplasm in stratified squamous epithelial cells , what will the neoplasm be called ?

Answer 23

Squamous papilloma ( has finger like projections)

Often in the buccal mucosa and skin.

Question 24

If there was a benign neoplasm in transitional epithelium , what would the neoplasm be called ?

Answer 24

Transitional cell papilloma

Often found in bladder mucosa

Question 25

If there was a glandular benign neoplasm , what will it be callled ?

Answer 25

Adenoma - but this is also further named based on their shape. For example villous shape , sessile shape and tubular shape.

If there is a benign neoplasm in ovary , it is called cystadenoma

Question 26

If there was an epithelial malignant neoplasm in stratified squamous , what will the neoplasm be called ?

Answer 26

Squamous cell carcinoma

This is often found in the skin , larynx , oesophagus , lung.

Question 27

If there was an epithelial malignant neoplasm in transitional epithelium , what will it be called ?

Answer 27

Transitional cell carcinoma

For example in the bladder and ureters

Question 28

If there was an epithelial malignant neoplasm in glands , what will It be called ?

Answer 28

Adenocarcinoma

For example in the skin, colon , lung , prostrate , breast , pancreas , oesophagus

Question 29

Smooth muscle benign neoplasm

Answer 29

Leiomyoma

Question 30

Fibrous tissue being neoplasm

Answer 30

Fibroma

Question 31

Bone benign neoplasm

Answer 31

Osteoma

Question 32

Cartilage benign neoplasm

Answer 32

Chondroma

Question 33

Fat benign neoplasm

Answer 33

Lipoma