Session 8 - Neoplasm 1 Flashcards Preview

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Flashcards in Session 8 - Neoplasm 1 Deck (70)
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0
Q

Define malignant neoplasm

A

Abnormal growth of cells which persists after the initial stimulus is removed AND invades the surrounding tissue with the potential to spread to distant sites

1
Q

Define neoplasm

A

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

2
Q

Define tumour

A

Any clinically detectable lump or swelling

3
Q

A neoplasm is a type of…

A

Tumour

4
Q

A cancer is any…

A

Malignant neoplasm

5
Q

What is a metastasis?

A

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

6
Q

Are tumours always neoplastic?

A

No, they can be either neoplastic of non-neoplastic

7
Q

Do neoplasms always form lumps?

A

No, some can be liquid tumours, eg leukaemia

8
Q

What is the original location of a neoplasm called?

A

Primary neoplasm

9
Q

What is a secondary site of a neoplasm?

A

The place to which the neoplasm has spread

10
Q

What is dysplasia?

A

A pre-neoplastic lesion in which cells show disordered tissue organisation and poor differentiation.

11
Q

What is the main difference between neoplasia and dysplasia?

A

Dysplasia is reversible, neoplasia is not

12
Q

How do benign neoplasm differ in behaviour from malignant?

A

Benign neoplasms are confined to the site of origin and do not produce metastases. Malignant neoplasms have the potential to metastasise

13
Q

How do benign tumours look to the naked eye?

A

Local confined area with an outer pushing margin which is regular

14
Q

When can benign tumours become dangerous?

A

When they are in areas which cannot compensate for them, or press against other structures eg the brain (space occupying lesion)

15
Q

How do malignant tumours appear to the naked eye

A

Irregular margins and shape with areas of necrosis and ulceration.

16
Q

Why does ulceration occur in malignant tumours?

A

Centre cannot get adequate blood supply and becomes necrotic, tumour breaks and necrotic tissue sloughs off with destruction of surface epithelial

17
Q

How do benign tumours appear microscopically?

A

Well differentiated without invasion

18
Q

How do malignant tumour appear microscopically?

A

Possible invasion of surrounding tissues/basement membrane. The differentiation can range from well to anaplastic.

19
Q

How do cells of a malignant neoplasm appear as the differentiation worsens?

A

Increased nuclear size and increased nuclear-cytoplasm ratio
Hyperchromasia
More mitotic figures with increased mitosis (sometimes abnormal)
Pleomorphism

20
Q

What is pleomorphism?

A

Cells which have increased variation in size and shape of cells and their nuclei, relative to each other.

21
Q

What does the term ‘grade’ indicate?

A

How differentiated the cells within a tumour are

22
Q

High grade tumours are…

A

Poorly differentiated

23
Q

Low grade tumours are…

A

Well differentiated

24
Q

What does the term anaplastic mean?

A

The cells of the tumour do not resemble any cell type.

25
Q

How does dysplasia lead to neoplasia?

A

The cell organisation and differentiation passes the pint of no return, ie it becomes irreversible

26
Q

What is an initiator?

A

Any mutagenic agent (intrinsic or extrinsic) which introduces a mutation into a cell

27
Q

What is a promoter?

A

Anyang which promotes the proliferation of the mutated population

28
Q

What is the end result of initiation and promotion?

A

An expanded monoclonal population of mutated cells

29
Q

Name some exogenous initiators

A

Chemicals
Infection
Radiation

30
Q

What is the advantage to neoplasm formation if there is an inherited/germline mutation?

A

The mutation does not have to occur from an external mutagenic agent, and thus initiation is skipped and the process can start at promotion

31
Q

What is progression?

A

The formation of a neoplasm from the expanded monoclonal population. Occurs by monoclonal cells acquiring another mutation, and this mutated cell being expanded forming a subpopulation. This process repeats several times (different amount required depending on where the neoplasm is)

32
Q

How is it possible to tell if a neoplasm is monoclonal in women?

A

All the cells in the tumour tissue would have the same isoenzyme of G6PD, in normal tissue there would be a patchwork of the isoenzymes dependant on the alleles in the woman.

33
Q

What is lyonisation?

A

Random inactivation of one allele during female embryogenesis

34
Q

In relation to neoplasms, what types of genes do genetic alterations usually effect?

A

Proto-oncogenes

Tumour-suppressor genes

35
Q

In relation to neoplasms, how are proto-oncogenes usually affected?

A

They are usually activated

36
Q

What effect does the activation of proto-oncogenes have and why?

A

It favours neoplasm formation as the genes effected are usually growth factors etc

37
Q

In relation to neoplasm formation, how are tumour-suppressor genes usually effected?

A

Both alleles are often deleted or inactivated

38
Q

How does deletion of tumour suppressor genes help neoplasm formation?

A

They normally suppress and control cellular proliferation and thus neoplasm formation. Without then there can be ku controlled proliferation

39
Q

Define carcinoma

A

A malignant neoplasm of epithelial origin

40
Q

Define adenocarcinoma

A

A malignant neoplasm of glandular epithelia

41
Q

What is meant by papilloma?

A

Finger-like projections

42
Q

What do most benign tumours end in?

A

-oma

43
Q

What do stromal malignant neoplasms end in?

A

-sarcoma

44
Q

What is meant by stromal?

A

Supporting tissues eg fibroblasts/smooth muscle

45
Q

What is mean by carcinoma-in-situ?

A

Carcinoma which hasn’t invaded and passed the basement membrane

46
Q

What is a leukaemia?

A

A malignant neoplasms of white blood cells which are circulating or in the bone marrow

47
Q

What is meant by lymphoma?

A

A malignant neoplasm of the lymphocytes which have accumulated in the lymph nodes

48
Q

What are the four types of leukaemia?

A

Chronic lymphocytic leukaemia
Acute lymphocytic leukaemia
Chronic myeloid leukaemia
Acute myeloid leukaemia

49
Q

Chronic lymphocytic leukaemia is…

A

Accumulation of mature B cells which have escaped apoptosis and undergone cell-cycle arrest

50
Q

Acute lymphocytic leukaemia is…

A

Malignancy effecting b and t lymphocyte cell lines, arresting maturation and promoting uncontrolled proliferation of immature blast cells with marrow failure

51
Q

Chronic myeloid leukaemia is…

A

Uncontrolled proliferation of myeloid cells

52
Q

Acute myeloid leukaemia is…

A

Neoplastic proliferation of myeloid blast cells

53
Q

What is a leiomyoma?

A

Benign tumour of smooth muscle

54
Q

What is a leiomyosarcoma?

A

Malignant tumour of smooth muscle

55
Q

What is a fibroma?

A

Benign tumour of fibroblast cells

56
Q

What is a fibrosarcoma?

A

Malignant tumour of fibroblast cells

57
Q

What is a myeloma?

A

Malignant neoplasm of plasma cells

58
Q

What is a germline neoplasm?

A

A tumour of the ovary or testis

59
Q

Are tumours of the testis usually benign or malignant?

A

Malignant

60
Q

What two groups can malignant testis tumours be separated into?

A

Seminomas

Non-seminoma germ line teratoma

61
Q

What are teratomas?

A

Tumours which are comprised of a number of tissues not found at the site of origin and usually arise in germline cells eg testis and ovaries

62
Q

Where else, except testis and ovaries, can teratomas occur and why?

A

Anywhere along the midline due to embryonic rest in migration in the embryo during formation

63
Q

What are neuroendocrine tumours?

A

Tumours which arise from cells distributed throughout the body

64
Q

What is characteristic about tumours which end in -blastoma?

A

Formed from immature precursor cells and usually occur in children

65
Q

What is a polyp?

A

An abnormal growth projecting from the mucous membrane

66
Q

How can colon cancer present as an emergency?

A

Bowel perforation-> cancer erodes through mucus membrane which leads to peritonitis

67
Q

How does obstruction occur in colorectal cancer?

A

Tumour grows so large that it causes an obstruction as the lumen is narrowed

68
Q

Do benign or malignant colorectal tumours often cause occlusion of vessels?

A

Benign. Malignant tumours erode

69
Q

In what situation could a benign tumour cause sudden pain?

A
  • If it outgrows it blood supply leading to infarction
  • occlusion of a vessel
  • if a pedunculated polyp becomes twisted, it will become infarcted