Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

SSC- Biology of Cancer > Role of the Lab in the Diagnosis and Management of Tumours > Flashcards

Role of the Lab in the Diagnosis and Management of Tumours Flashcards

1
Q

What is the gold standard in the diagnosis of cancer?

A

Histology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What % of the work of a histology lab is convered with the diagnosis and treatment of cancer?

A

70%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why is it important that cancer diagnoses are made correctly?

A

False positives and negatives are potentially disastarous and expensive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Why might false positive cancer results be disasterous?

A

A diagnosis of cancer can lead to radical treatment that is disfiguring or harmful

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Why can false negative cancer results be potentially disastrous?

A

Because the patient will come back with more advanced tumours with a worse prognosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why are most cancers easily diagnosed histologically?

A

Because most cases show histological features that are at either end of the benign-malignant spectrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What happens when cases are in the middle of the benign-malignant spectum histologically?

A

It produces problems of diagnosis, and therefore management

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the categories of samples sent for cancer diagnosis?

A
  • Tissue
  • Cytology
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What forms of tissue sample might be received for histological testing?

A
  • Diagnostic biopsy
  • Excisional specimen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the main purpose of diagnostic biopsies?

A

Diagnosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Give two examples of methods of obtaining diagnostic biopsies

A
  • Incisional
  • Needle core
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the main purpose of obtaining excisional specimens

A

Done with curative intent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What tissues are amenable to histological evaluation?

A

All

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is evaluated in cytology?

A

Cells suspended in fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the ways of obtaining cytology samples?

A
  • Exfoliation
  • Aspiration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How can cells be exfoliated?

A
  • Can be shed - cells fall off a surface
  • Can be scraped off a surface
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Give 4 examples of fluids that cells are shed into

A
  • Sputum
  • Urine
  • Pleural
  • Ascitic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the problem with using cells that have been shed in diagnosis?

A

Cells usually degenerate, so cancer pick-up rate is low

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How does the pick-up rate of cancer differ between shed cells and scraped cells?

A

The scraped cells are intact and viable, so the pick-up rate is higher

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

When is an aspirate sample taken?

A

When no surface is available for exfoliation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Give 3 locations that an aspirate sample would be taken from

A
  • Accessible lump
  • Breast
  • Lymph node
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How is an aspirate sample collected? al

A

With a needle into a lump, free hand - without guidance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How is an aspirate sample collected?

A

Under imaging guidance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Give three locations where an aspirate sample would be obtained

A
  • Inaccessible lump
  • Liver
  • Pancreas
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is initially reported on when a histologist obtains a specimen?

A

A macroscopic description of;

  • Tumour
  • Apperance
  • Size
  • Spread
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Why is tissue resected during cancer surgery inked?

A

To demonstrate the excision margin when you look at it down the microscope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What happens if a cancer extends to the excision margin?

A

Probably need further treatment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How is the tumour specimen further divided from its original form?

A

Blocks are taken from areas of interest

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What happens to the tissue blocks cut from the specimen?

A

They are impregnanted with wax to support tissue, and 4μm sections are cut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How are the 4μm sections prepared for microscope visualisation?

A

They are mounted on a glass slide and stained

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What factors will the histology report consider?

A
  • Is there a lesion?
  • Is it malignant?
  • What sort of malignancy?
  • How malignant is it? (Grade)
  • How far has it spread? (Stage)
  • Is it all out?
32
Q

What are the categories in the histological criteria of malignancy?

A
  • Tissue changes
  • Cytological changes
33
Q

What are the tissue changes in the histological criteria of malignancy?

A
  • Dysplasia
  • Invasion
  • Infiltrative margin
34
Q

What are the cytological changes in the histological criteria of malignancy?

A
  • Nuclear pleomorphism
  • Nuclear size
  • Nuclear shape
  • Nuclear staining
  • Increased proliferation
  • Increased number of mitotic figures
  • Abnormal mitotic figures
35
Q

What are tumours named from?

A

The tissue in which they are derived

36
Q

What are the potential histogenic classifications of tumours?

A
  • Squamous
  • Glandular
  • Lymphoid
  • Melanocytic
37
Q

What kind of classification may be more useful than histogenic classification in the future?

A

Molecular classification, e.g. Braf +ve, HPV associated etc

38
Q

Histologically, what can help determine what sort of malignancy it is?

A
  • Architectural arrangement
  • Cytological differentiation
39
Q

What features are considered in cytological differentiation?

A
  • Morphology
  • Protein expression
40
Q

What may be found when looking at morphology of malignant cells?

A
  • Desmosomes
  • Mucin
  • Melanin
41
Q

What may be found when looking at protein expression in malignant cells?

A
  • Filaments
  • Low or high molecular weight cytokeratins
  • Specific protein products
  • Thyroglobulin
  • Enzyme production
42
Q

What is the importance of the cancers grade?

A

It provides important prognostic information about some cancers

43
Q

What is a cancer grade based on?

A

Degree of differentiation

44
Q

How is a cancer grade determined?

A

Mixture of score and subjective assessment, considering;

  • Proliferation
  • Architectural differentiation
  • Pleomorphism
45
Q

What is the best predictor of prognosis in most cancers?

A

Stage

46
Q

What does stage consider?

A

The extent of the spread

47
Q

What is the importance of knowing the cancer stage?

A

It provides vital information for making management decisions

48
Q

Where to carcinomas spread to first?

A

Lymph nodes

49
Q

Where do sarcomas spread to first?

A

Blood stream

50
Q

How do sarcomas spread?

A

Via the blood stream

51
Q

What needs to be assessed in order to determine the cancer stage?

A
  • Primary tumour
  • Draining lymph nodes
  • Distant spread
52
Q

What happens when you cannot assess the primary tumour?

A

It is considered to be Tx

53
Q

What happens if lymph nodes are found to be involved in cancer?

A

Clearance

54
Q

What happens if no involved nodes are found on examination or imaging?

A

Targeted lymph node sampling

55
Q

What is typically done to lymph nodes in breast cancer?

A

Axillary clearance

56
Q

What is the problem of axillary clearance treatment in breast cancer?

A

There is significant morbidity from lymphoedema

57
Q

When is sentinal lymph node biopsy conducted in breast cancer?

A

In clinical and USS negative cases

58
Q

What cancers is sentinal lymph node biopsy routinely used for?

A
  • Breast
  • Melanoma
  • Penile SCC
  • Head and neck SCC
59
Q

What happens in a sentinal lymph node biopsy?

A

You inject the tumour with a dye containing a short half life radioactive isotope to determine the first draining lymph node. You would then remove and assess this lymph node. If there is no cancer, then the patient does not need a lymph not clearance. If there is, need lymph node clearance

60
Q

What should be reported on when considering the margins in cancers?

A

How big the margins are, and if the margins are cleared, close, or involved

61
Q

When might the margins in cancer exicision be left intentionally small?

A

When there is intent for plastic surgery - have to balance getting clearance with serious deformity

62
Q

Give an example of a technique that can be employed when trying to make margins as small as possible

A

Moh’s micrographic surgery

63
Q

What happens when the margins are involved?

A

Further excision or radiotherapy

64
Q

Other than light microscopy, what other lab techniques can be used to investigate a tumour?

A
  • Histochemical stains
  • Electron microscopy
  • Immunohistochemistry
  • PCR
  • In situ hydridisation
  • Cytogenetics
65
Q

How can histochemical stains be useful in the diagnosis of cancer?

A
  • Can help characterise the tissue components, e.g. collagen, melanin
  • Can detect infection
66
Q

How can PCR be useful in the diagnosis of cancer?

A
  • Can detect monoclonality
  • Can detect some infections
67
Q

How can in situ hybridisation be useful in diagnosing cancer?

A

Can use specific probes for RNA or DNA to detect clonality

68
Q

What can be looked for using cytogenetics?

A

Translocations

69
Q

How is immunohistochemistry conducted?

A
  1. Antibodies bind to specific proteins in tissues, and so can be applied to tissue sections and detected via colour producing peroxidase reaction
  2. Antigens of interest are injected into animals to stimulate the immune response
70
Q

What can biological markers be used to determine?

A

Therapy

71
Q

How can protein expression be characterised in the lab?

A

Using immunohistochemistry

72
Q

Give an example of where steroid receptor status might be important

A

Breast cancer - oestrogen receptor expression predicts response to hormone therapy

73
Q

Why does oestrogen receptor expression predict the response to hormone therapy?

A

Because some tumours are dependant on oestrogen for growth (oestrogen regulates genes that promote growth), and detection of nuclear receptor indicates oestrogend dependance. If the tumour is dependant on oestrogen, blocking it will cause its death

74
Q

What is HER-2?

A

A member of the ECG receptor family. It is a tyrosine kinase which promotes cell growth

75
Q

What % of breast cancers have HER-2 gene amplification?

A

20-30%

76
Q

What does gene amplification of HER-2 lead to?

A

Uncontrolled cell growth

77
Q

Why is it important to know HER-2 status in breast cancer?

A
  • HER-2 overexpression is a poor prognostic marker
  • Monoclonal antibodies to Her 2 inhibits Her 2 activity, and this treatment (herceptin) leads to a dramatic improvement in survival

SSC- Biology of Cancer (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions