Pathology: CANCER Flashcards
1
Q
- What is the definition of a tumour?
A
Any abnormal swelling. Could mean a neoplasm or could be the result of inflammation/ hypertrophy/ hyperplasia
2
Q
- What is the definition of a neoplasm?
A
A lesion resulting from the autonomous or relatively autonomous abnormal growth of cells, which persists after the initatiting stimulus has been removed – a new growth. Neoplasms may be benign (not cancer) or neooplasms may be malignant (cancer)
3
Q
- What does autonomous refer to?
A
Not regulated by normal homeostatic feedback loops – autonomous
4
Q
- What does persistant refer to?
A
Normally growth is driven by cell signalling and if you were to take away those drivers the cell would stop growing. In neoplasia this is not the case , stopping the stimulus will not stop the growth of the cancer
5
Q
- Why does the risk increase with age?
A
More time to be exposed to carcinogens and survive the latent interval
6
Q
- Why is there a fall in the incidence of cancer in >80 yr olds?
A
Fewer people aged 80
7
Q
- What proportion of deaths does cancer account for?
A
20% of all deaths in UK
8
Q
- What is the most common cancer in men in the UK?
A
Prostate
9
Q
- What is the most common cancer in women in the UK?
A
Breast
10
Q
- What is the most common cause of cancer death in men in the UK?
A
Lung
11
Q
- What is the most common cause of cancer death in women in the UK?
A
Lung
12
Q
- Are all neoplasms cancer?
A
No – it is a spectrum of disease that ranges from benign to malignant
13
Q
- Is it just benign or malignant neoplasms?
A
No – there is a borderline category
14
Q
- Are all neoplasms fatal?
A
No some are subclinical , it is also a range , even within an individual cancer
15
Q
- What cancer has a wide range of disease burden?
A
- Prostate cancer – some men will die with prostate cancer but never know they had it. Some men will survive with prostate cancer.
- Thyroid cancer
16
Q
- What are the two components of a neoplasm?
A
- Neoplastic cells – cells that have changed as a result of exposure to carcinogens, accumulates series of mutations
- Stroma – connective tissue that supports the neoplastic cells
17
Q
- What cancer is the exception to general structure and components of a neoplasm?
A
Leukaemia
18
Q
- What do all neoplastic cells derive from?
A
Nucleated cells
19
Q
- Why do neoplastic cells always derive from nucleated cells?
A
Bc cancer (and also benign neoplasms) always derive from DNA mutations
20
Q
- What does monoclonal mean?
A
All carry the same set of mutations -DNA
21
Q
- What happens with time to these neoplastic cells?
A
Change from monoclonal –> polyclonal , each cell can accumulate diff mutations
22
Q
- What is the neoplastic cell process?
A
- Initially - derive from nucleated cells, usually monoclonal
- Growth
- Synthetic activity – collagen, mucin, keratin , hormones etc
23
Q
- What is the growth pattern of neoplastic cells like?
A
Related to the parent cell – to a certain degree
24
Q
- What is the synthetic activity of neoplastic cells related to?
A
To parent cell but are autonomous so can continue to produce hormones when no signals given etc e.g a benign neoplasm in the thyroid can cause hyperthyroidism
25
31. What is the stroma of the neoplasm?
May be epithelial or derive from connective tissue
26
32. What is the function of the stroma?
* Mechanical support (framework)
| * nutrition – ingrowth of new blood vessels
27
33. What cell and tissue types would you therefore expect to find within a neoplasms stroma? Consider an Andenocarcinoma of the breast:
Histological appearance:
• Duct structures – ductal adenocarcinoma of the breast
• Dark purple areas- Neoplastic cells (malignant ductal epithelial cells of breast)
• Pale pink material – Stroma, fibroblast cells producing lots of extracellular collagen
• New blood vessels
28
35. What is angiogenesis?
Ingrowth of new blood vessels
29
36. Why is angiogenesis necessary for neoplasms
Growth
30
37. What is the growth rate of neoplasms compared to normal tissue?
Faster and more uncontrolled, but is limited by angiogenesis
31
38. What is angiogenesis promoted by?
Various factors such as Vascular endothelial growth factor
32
39. What is the size of the neoplasm without angiogenesis?
Limited to about 2mm diameter – bc maximum diameter that oxygen and nutrients can diffuse into the neoplasm by simple diffusion from blood vessels outside the neoplasm
33
What limits the size of a neoplasm
Angiogenesis. Without angiogenesis limited to 2mm diameter (bc max size that diffusion will be able to supply)
34
40. What is the rate of malignant neoplasia growth compared to angiogenesis?
•Malignant neoplasia grows at a FASTER rate compared to angiogenesis
35
Since malignant neoplasia grow at a faster rate compared to angiogenesis, what is a consequence of this for the malignant neoplasia?
The centre of a malignant neoplasm often dies -Necrosis. You get vascularised tumour with central necrosis
36
Why do many malignant neoplasias have a vascularised tumour with central necrosis?
•Malignant neoplasia grows at a FASTER rate compared to angiogenesis
37
43. Why do we classify neoplasms?
* So professionals can easily share info
* To provide prognostic info
* To determine appropriate treatment
38
44. What are the methods of classification of neoplasia?
* Behavioural – benign/ malignant
* Histogenetic – apparent cell of origin
Clinically both methods are used
39
46. What are the catagories of behavioural classification for neoplasms?
* Most neoplasms are benign or malignant
| * Some are borderline
40
What neoplasms can be borderline?
* Ovarian lesions
| * Carcinoid tumours – tumours of neuroendocrine cells
41
48. Why do some ovarian lesions defy precise classification?
Look down the microscope as Benign but they behave in a malignant fashion.
42
49. Why do carcinoid tumours defy precise classification?
Look benging but behave ,malignantly , classified as malignant
43
50. What are common features of benign neoplasms?
* Localised, non-invasive
* Slow growth rate
* Low mitotic activity - no mitotic figures/ few in microscopy
* Close resemblance to normal tissue
* Circumscribed or encapsulated – push the tissue around them out of the way, condense into a capsule around edge of neoplasm
44
What is a very common benign neoplasm of the uterus?
Uterine fibroid
45
51. What is a uterine fibroid?
Very common benign neoplasm of the uterus
46
52. What is the histological appearance of a uterine fibroid?
Looks like smooth muscle , all of the material on the left is a neoplasm and the smooth muscle on the right is normal
47
53. What is a tubulovillous adenoma?
A benign neoplasm from the intestine
48
54. What is the histological appearance of a tubulovillous adneoma?
Nuclei look normal, no necrosis – it is rare, no ulceration- it is rare, growth on mucosal surfaces, often exophytic
49
55. Are benign neoplasms a clinical worry?
They can cause morbidity and mortality by:
• Pressure on adjacent structures
• Obstruct flow
• Production of hormones
• Transformation to malignant neoplasm (debate about this)
• Anxiety
50
56. What are the defining features of malignant neoplasms?
* Invasive
* Metastases
* Rapid growth rate (more than benign neoplasms)
* Variable resemblance to normal tissue
* Poorly defined or irregular border . (In benign -like fibroid, there is a defined border)
* Are poorly circumscribed – have a ‘crab like’ cut surface – latin name is cancer
51
57. Describe the histological appearance of this prostate cancer, how can you tell it’s a cancer?
Cancer on the left of image and normal on right, no border between, cancer infiltrating the surrounding connective tissue – poorly defined, irregular border. Invasive growth factor
52
What implications does poorly defined irregular border, which is present In malignant neoplasms have for treatment?
Less easy to remove
53
61. What are the other histological features of malignant neoplasms?
* Abnormal nuclei – hyperchromatic nuclei, pleomorphic nuclei
* Increased mitiotic activity – mitotic figures
* Necrosis common
* Ulceration common if growing on mucousal surface
* Growth on mucosal surfaces and skin often endophytic (grow down into underlying tissue)
54
What is endophytic growth - is this more common with benign or malignant neoplasia?
Growing down into the underying tissues. Feature of malignant neoplasia
55
62. What is the worry about malignant neoplasms - how do they cause morbidity and mortality?
* Encroach upon and destroy surrounding tissue
* Can metastasise – secondary deposits at other distant sites can actually cause more disease than the primary cancer
* Blood loss from ulcers
* Obstruction of flow – bowel obstriction , urinary tract obstruction
* Hormone production
* Paraneoplastic effects – due to proteins and other substances produced
* Anxiety and pain
56
63. Why can cancer become painful?
If it invades the nerves in the underlying tissues
57
64. When is cancer pain evident
Often a late symptom
58
67. How is the histogenetic classification of a neoplasm determined?
Need to examine tumour under the microscope
59
68. What is the dichotomy of connective tissue neoplasms?
Not necessarily true that a neoplasm of fat has arisen from a fat cell etc - refers to connective tissue neoplasms
60
69. Where do connective tissue neoplasms arise from then?
More likely that they derive from less differentiated Mesenchymal cells, which have the potential to become fat cells, blood vessels, smooth muscle cells etc
61
70. What can neoplasms arise from?
* Epithelial cells – most common type
* Connective tissues
* Lymphoid/ Haematopoietic organs
62
What is the most common cell type that neoplasm arises from?
Epithelial cells
63
71. What are the components of Neoplasm nomenclature?
* All neoplasms have the suffix ‘-oma’
| * Prefix depends on behavioural classification + cell type
