Neoplasms 1 Flashcards Preview

ESA 2- Mechanisms of Disease > Neoplasms 1 > Flashcards

Flashcards in Neoplasms 1 Deck (71):
1

What is a neoplasm?

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

2

What must be true for a neoplasm to grow without continuation of the stimulus?

Some degree of autonomous growth

3

What is a malignant neoplasm?

A neoplasm that invades the surrounding tissue with the potential to spread to a distant site

4

Is hyperplasia reversible?

Yes

5

What causes neoplasia?

Genetic alterations

6

It neoplasia reversible?

No

7

What is a tumour?

Any clinically detectable lump or swelling

8

Is a neoplasm a tumour?

Yes, but just one type

9

What is a cancer?

Any malignant neoplasm

10

What is a metastasis?

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

11

What must be true of the spread of a malignant neoplasm?

It cannot be due to direct spread, it must have some sort of transport mechanism

12

What is the primary site?

The original location of the tumour

13

What are the places a cancer has spread to called?

Secondary sites

14

What is dysplasia?

A pre-neoplastic alteration in which cells show disordered tissue organisation

15

Why is dysplasia not neoplastic?

Because the change is reversible

16

What can dysplasia lead to?

Neoplasia

17

What is the difference between benign and malignant neoplasms?

They show different behaviour

18

What behaviour do benign neoplasms show?

They remain confined to their site of origin, and do not produce metastases

19

Are benign neoplasms symptomatic?

They may or may not be, depending on location

20

When may benign neoplasms cause symptoms?

If at a critical site, for example a small space

21

What do malignant neoplasms have the potential to do?

Metastasise

22

What is the problem with malignant neoplasms metastasising?

There is an ever increasing tumour burden, the tumour spreads to make new tumours, which then have the potential to make new tumours too

23

What do benign tumours do?

Push and squash

24

What do malignant tumours do?

Invade and destroy

25

How do benign tumours appear to the naked eye?

They grow in a confined local area and so have a pushing outer margin

26

How do malignant tumours appear to the naked eye?

They have an irregular, jagged outer margin and may show areas of necrosis and ulceration (if on surface)

27

Why do malignant tumours show areas of necrosis?

Often, bits of tumour are growing faster than the blood supply, so undergo ischaemic death

28

Why do malignant tumours cause ulceration?

They cause a break in the surface

29

What do neoplasms show under the microscope?

Varying degrees of differentiation

30

How do benign tumours appear under the microscope?

They have cells that closely resemble the parent tissue, i.e. they are well differentiated

31

How do malignant neoplasms appear under the microscope?

They range from well to poorly differentiated

32

What are cells that have no resemblance to any tissue called?

Anaplastic

33

What happens to cells with worsening differentiation?

They have increasing nuclear size and nuclear to cytoplasmic ratio
Increased nuclear staining 
More mitotic figures 
Increasing variation in size and shape of cells and nuclei

34

What does an increase in nuclear size reflect?

A change in chromosomes

35

What is increased nucleur staining known as?

Hyperchromasia

36

What is a variation in size and shape of nuclear staining called?

Pleomorphism

37

How do clinicians indicate differentiation?

In grades, with high grade being poorly differentiated

38

What does dysplasia represent?

Altered differentiation

39

What indicates worsening differentiation?

Mild, moderate and severe dysplasia

40

What is neoplasia caused by?

Accumulated mutations in somatic cells

41

What are mutations caused by?

Initiators and promoters

42

What are initiators?

Mutagenic agents

43

What do promoters cause?

Cell proliferation

44

What do initiators and promotes result in, in combination?

An expanded, monoclonal population of mutant cells

45

What are the main initiators?

Chemicals 
Infections 
Radiation

46

Can chemicals, infections and radiation act as promoters?

Some can

47

How can mutations be obtained in some neoplasms?

Inherited, rather than from an external mutagenic agent

48

How does a neoplasm emerge from a monoclonal population?

Through a process called progression

49

What is progression characterised by?

Accumulation of yet more mutations

50

When is a collection of cells monoclonal?

If they all originated from a single founding cell

51

Where does evidence that neoplasms are monoclonal come from?

The study of the X-linked gene for the enzyme glucose-6-phosphate dehydrogenase (G6PD) in tumour tissue in women

52

How does the G6PD gene provide evidence that neoplasms are monoclonal?

The gene has several alleles encoding different isoenzymes. Early in female embryogenesis, one allele is randomly inactivated in each cell (lyonisation). In heterozygous women that happen to have one allele encoding a heat stable isoenzyme and one heat lable isoenzyme, normal tissue will be a patchwork of each type. However, neoplastic tissues only express on isoenzyme indicating a monoclonal group of cells

53

What do genetic alterations affect?

Proto-oncogenes and tumour supressor genes

54

What happens to proto-oncogenes that causes neoplasms?

They become abnormally activated

55

What are proto-oncogenes called when they are activated?

Oncogenes

56

What do tumour suppressor genes normally do?

Suppress neoplasm formation

57

What happens to tumour suppressor genes that causes neoplasms?

They become inactivated

58

What does the organised system for naming neoplasms take into account?

A neoplasms site of origin, wether it is benign or malignant, the type of tissue the tumour forms and sometimes the gross morphology (e.g. a cyst or papilloma_

59

What do benign neoplasms end in?

#NAME?

60

What do malignant neoplasms end in?

-carcinoma if its epithelial 
-sarcoma if its a stromal malignant neoplasm

61

What % of malignant tumours are epithelial?

90%

62

What can carcinomas be?

In situ 
Invasive

63

What is meant by a tumour being in situ?

There is no invasion through the basement membrane

64

What is meant by a tumour being invasive?

It has penetrated through the basement membrane

65

What is leukaemia?

A malignant neoplasm of blood-forming cells arising in the bone marrow

66

What are lymphomas?

Malignant neoplasms of lymphocytes, mainly affecting lymph nodes

67

What is myeloma?

A malignant neoplasm of plasma cells

68

What do germ cells neoplasms arise from?

Pluripotent cells, mainly in the testis or ovary

69

What do neuroendocrine tumours arise from?

Cells distributed throughout the body

70

Who do -blastomas mainly occur in?

Children

71

What are -blastomas formed from?

Immature precursor cells