Pathology Flashcards
(219 cards)
1
Q
What is a thrombus?
A
The solidification of blood contents that forms within the vascular system during life
2
Q
What are platelets derived from?
A
Megakaryotes
3
Q
What granules do platelets contain and what do they do?
A
Alpha granules- platelet adhesion
Dense granules- platelet aggregation
4
Q
What activates platelets?
A
Contact with collagen
5
Q
What causes a thrombus to occur?
A
When platelet aggregation occurs in an intact vessel
6
Q
Why is platelet aggregation difficult to stop?
A
Causes the clotting cascade to begin which is a positive feedback loop
7
Q
What ideology do we use to discuss causes of thrombosis?
A
Virchow’s Triad
8
Q
What are the 3 groups in Virchow’s Triad? Give examples for each.
A
- Reduced blood flow: AF, long travel, immobility, ventricular insufficiency
- Increased coagulability: sepsis, smoking, malignancy, coagulation disorder
- Blood vessel injury: trauma, surgery, hypertension
9
Q
What prevents blood clotting in normal circumstances?
A
Laminar blood flow
Endothelium cells are not sticky when healthy
10
Q
What are the constituents of a thrombus?
A
Platelets, RBCs, Fibrin
11
Q
What is the inactive form of fibrin?
A
Fibrinogen
12
Q
What causes arterial thrombosis vs venous thrombosis?
A
Arterial thrombosis: caused by atheromatous plaque
Venous thrombosis: caused by stasis of blood flow
13
Q
Describe how an arterial thrombus forms.
A
- Atheromatous plaque may have fatty streak
- Plaque grows and protrudes into the lumen causing turbulence to blood flow
- Turbulence causes loss of intimal cells
- Fibrin deposition and platelet clumping occurs
- This is self-perpetuating and leads to formation of platelet layer (first later of thrombus)
- Fibrin precipitates and RBCs get trapped
- Structure protrudes further into lumen causing more turbulence and more platelet deposition
- Thrombi grow in direction of blood flow- propagation
14
Q
Describe how a venous thrombus forms.
A
- Valves produce a degree of turbulence and can be damaged
- When blood pressure falls, flow through the vein slows which allows thrombus to form
15
Q
Where in the vein does a thrombus typically form and why?
A
At the value due to turbulence to blood flow
16
Q
Why does atheroma not occur in veins?
A
Blood pressure is too low
17
Q
How does an arterial thrombus display clinically?
A
Loss of pulse due to distal thrombus
Area is cold, painful and pale
Possible gangrene
18
Q
How does a venous thrombus display clinically?
A
Area is tender
Reddened and swollen
19
Q
What can be prescribed to inhibit platelet aggregation?
A
Aspirin
20
Q
Describe the 4 possible outcomes of thrombosis.
A
- RESOLVE
- Best case scenario
- Body dissolves thrombus and clears it - ORGANISED
- Becomes a scar
- Slight narrowing of vessel lumen - RECANALISATION
- Intimal cells may proliferate
- Capillaries may grown into the thrombus and fuse to form larger vessels - EMBOLUS
- Fragments of thrombus break off into circulation
20
Q
Describe the 4 possible outcomes of thrombosis.
A
- RESOLVE
- Best case scenario
- Body dissolves thrombus and clears it - ORGANISED
- Becomes a scar
- Slight narrowing of vessel lumen - RECANALISATION
- Intimal cells may proliferate
- Capillaries may grown into the thrombus and fuse to form larger vessels - EMBOLUS
- Fragments of thrombus break off into circulation
21
Q
What is the difference in composition of an arterial and venous thrombus?
A
Arterial- mainly platelets
Venous- mainly RBCs
22
Q
What can arterial thrombosis lead to if untreated?
A
Myocardial Infarction
Stroke
23
Q
What can venous thrombosis lead to if untreated?
A
Deep vein thrombosis
Pulmonary embolism
24
What is prescribed for arterial and venous thrombosis?
Arterial- antiplatelets (e.g. aspirin)
Venous- anticoagulants (e.g. warfarin)
25
What are the 2 types of inflammation?
Acute & chronic
26
What is acute inflammation?
Initial response of a tissue to injury
Early onset
Short duration
Involved neutrophils and monocytes
27
What are the 3 main steps of acute inflammation?
1. VASCULAR component: dilation of vessels
2. EXUDATIVE component: vascular leakage of protein rich fluid
3. NEUTROPHIL polymorph: cell type recruited to tissue
28
What are the 6 causes of acute inflammation?
Microbial infections
Hypersensitivity reactions
Physical agents (trauma, heat, etc.)
Chemicals (corrosives etc.)
Bacterial toxins
Tissue necrosis
29
Describe the appearance of acute inflammation.
Rubor- redness
Calor- heat
Tumor- swelling
Dolor- pain
Loss of function
30
What causes rubor in acute inflammation?
Dilation of small vessels
31
Describe neutrophil polymorph emigration in acute inflammation.
1. Migration of neutrophils:
Due to increase plasma viscosity and slowing of flow due to injury, neutrophils migrate to plasmatic zone
2. Adhesion of neutrophils:
Adhesion to the vascular endothelial cells occurs in venules- this is called pavementing
3. Neutrophil emigration:
Neutrophils pass through endothelial cells, onto basal lamina and then the vessel wall
4. Diapedesis:
Neutrophils pass through blood vessel. RBCs may also escape from vessels. This is a passive process and indicates severe vascular injury
32
Describe the outcomes of acute inflammation.
1. RESOLUTION:
- complete restoration of tissues to normal
- minimal cell death and rapid destruction of the causal agent
2. SUPPORATION:
- formation of pus
- this becomes surrounded by a pyogenic membrane, which is the start of healing
3. ORGANISATION:
- replacement by granulation tissue
- new capillaries grow into inflammatory exudate, macrophages migrate and fibrosis occurs
4. PROGRESSION
- causative agent is not removed so there is progression to chronic inflammation
33
What is the difference between how bacteria and viruses cause harm?
bacteria- release of exotoxins/ endotoxins
virus- call death due to intracellular multiplication
34
What are the systemic affects of acute inflammation?
pyrexia
weight loss
reactive hyperplasia of reticuloendothelial system
haematological changes
amyloidosis
35
What are the endogenous chemical mediators of acute inflammation and what do they do?
Bradykinin, histamine, nitric oxide
They lead to vasodilation, recruitment of neutrophils, chemotaxis, increased vascular permeability, itching, pain
36
List the cell types involved in acute inflammation and whether they are short or long lived.
Neutrophil polymorph- short
Macrophage- long
Lymphocyte- long
Fibroblasts- long
Endothelial cells- long
37
What is the general function of neutrophil polymorphs in acute inflammation?
- first at scene
- dies at scene
- releases chemicals that attract macrophages
38
What is the general function of macrophages in acute inflammation?
- phagocytic properties
- ingests bacteria and debris (prevent infection)
- may present antigens and lymphocytes
39
What is the general function of lymphocytes in acute inflammation?
- produce chemicals that attract inflammatory cells
- immunological memory for past infections and antigens
40
What is the general function of fibroblasts in acute inflammation?
- forms collagen in areas of chronic inflammation to aid repair
41
What is the general function of endothelial cells in acute inflammation?
- sticky so inflammatory cells adhere
- porous to allow inflammatory cells to pass into tissues
- grow in areas of damage to form new capillaries
42
What is chronic inflammation?
- subsequent and prolonged response to tissue injury
- involves lymphocytes, macrophages and plasma cells
- longer onset
- longer lasting effects
43
What is the name for several macrophages joined together?
multinucleated giant cell
44
What are the causes of chronic inflammation?
- endogenous/ exogenous materials (necrosis, asbestos)
- autoimmune conditions
- transplant rejection
- recurrent acute inflammation
- progression from acute inflammation
45
How does chronic inflammation present macroscopically and microscopically?
MACROSCOPIC:
- chronic ulcer
- chronic abscess cavity
- granulomatous inflammation
- fibrosis
MICROSCOPIC:
- lymphocytes, plasma cells, macrophages
- possible tissue necrosis
- continuing destruction
46
Which cell is present in chronic inflammation but not acute?
Plasma cells
47
Describe the role of lymphocytes and macrophages in chronic inflammation.
B lymphocyte:
- transforms into plasma cells
- produce antibodies
T lymphocytes:
- cell-mediated immunity
Macrophages:
- respond to chemotactic stimuli
- produce cytokines
48
Which cytokines are produced in chronic inflammation?
interferons:
alpha
beta
IL6, IL7, IL8
TNF-alpha
49
What is granuloma?
aggregate of epithelioid
50
In what type of inflammation can granuloma occur?
chronic
51
What is an embolism?
A mass of material in the vascular system able to lodge in a vessel and block it's lumen
52
What can form an embolus?
- thrombus
- air
- cholesterol crystals
- tumour
- amniotic fluid
- fat
53
Where can arterial embolisms travel? Are there any exceptions to this?
Anywhere downstream of its entry point
Mural thrombi in left ventricle can go anywhere
Cholesterol crystals from atheromatous plaque in descending aorta can go anywhere
54
What is another name for an arterial embolism?
Systemic embolism
55
Where do emboli in the venous system travel?
Travel to the vena cava and lodge in pulmonary arteries = pulmonary embolism
56
Describe the different sizes of emboli.
1. Small emboli:
- may occur unnoticed
- can cause idiopathic pulmonary hypertension
2. Large emboli:
- can result in acute respiratory or cardiac problems
- resolve slowly
- result in chest pain and shortness of breath
3. Massive emboli:
- sudden death
- arise from long thrombi derived from leg veins
- often impacted across the bifurcation of one of the pulmonary arteries
57
What does idiopathic mean?
Any disease or condition which arises spontaneously or for which the cause is unknown
58
What is ischaemia?
reduction of blood flow to a tissue or part of the body caused by constriction or blockage of the blood vessels supplying it
does not result in any further complications by itself
59
How long are ischaemic attacks?
brief (usually 1 hr, max 24 hrs)
60
Which cells are most vulnerable to ischaemia?
cardiomyocytes
cerebral neurons
61
Is ischaemia reversible?
yes
62
What is infarction?
reduction in blood flow that leads to cell death due to an inadequate oxygen supply to sustain metabolic demand
63
What usually causes infarction?
arterial thrombosis
64
Which organs are least susceptible to infarction and why?
Liver, brain and lungs
They are the only organs with a dual blood supply
65
What is a reperfusion injury?
damage to tissue during deoxygenation after an infarct
66
What causes retinoblastoma?
A gene inherited on chromosome 13
67
What is the meaning of resolution in terms of healing?
- tissue restored to normal, pre-injury state
- tissue architecture undamaged (able to regenerate)
- initiating factor (cause of injury) is removed
68
What is the meaning of repair in terms of healing?
- tissue is repaired, but unable to regenerate to pre-injury state- replaced with scar/ fibrotic tissue
- tissue architecture is damaged- unable to regenerate
- initiating factor still present
69
Which cells can regenerate?
hepatocytes
pneumocytes
blood cells
gut epithelium
skin epithelium
osteocytes
70
Which cells can't regenerate?
myocardial cells
neurones
71
Give some examples of repair
- myocardial cell after MI
- neurones in brain after cerebral infarct
- neurones in spinal chord after trauma
72
How does the liver heal? What if damage is repeated? e.g. chronic alcoholism
- hepatocytes can fully regenerate (resolution) is damage is not repeatedly occurring
- if damage is repeated (patient keeps drinking) repair will occur instead of resolution leading to fibrous scarring, regenerative nodules and eventually cirrhosis
73
What is fibrosis?
scarring
74
How is fibrosis classified?
Staging system ranging from 1 to 4
75
What is cirrhosis?
Stage 4 fibrosis
76
How does fibrosis affect tissues?
As fibrosis progresses, normal functional tissue is replaced by scar tissue (not functional)
77
How does cirrhosis affect the liver?
- alteration of blood flow
- inability to synthesise proteins
- inability to process drugs and toxins
- decreased immune function
78
What is lobar pneumonia?
bacterial infections in one lobe of the lungs caused by strep pneumonia
one lobe of lungs fills with pus
alveoli fill with neutrophil polymorphs
79
Can alveoli regenerate after global pneumonia?
pneumocystis of alveoli can regenerate as long as infection/pus has cleared
resolution can occur in walls of alveoli if architecture is intact
80
How does COVID-19 affect the lungs?
- interstitial pneumonia affecting more than one lobe
- interstitium and connective tissue of lungs fill with fluid- patchy appearance on chest x-ray
- severe COVID can destruct alveoli architecture, leading to fibrosis- presents as honeycomb lung
81
How do skin abrasions heal?
repair- as long as skin has been scraped and no hole has been made
82
Describe the process of skin repair.
- top stratified layer of squamous epithelial cells are scraped off to expose stem cells underneath
- these stem cells regenerate the skin underneath the scab
- initially a thin confluent epidermis forms before being replaced by final epidermal growth
83
How does skin heal if the stem cells are removed in the abrasion?
The skin will regenerate via the stem cells associated with hair follicles
84
What is the difference between healing by first and second intention?
Healing by first intention occurs in surgical incisions or wounds with close edges whereas healing by second intention occurs when you cannot bring the edges together due to a gap or hole in the skin
85
Describe the process of healing by first intention
1. edges are brought together using stitches
2. incision would fills with blood and a thrombus forms
3. exudation of fibrinogen causes formation of weak fibrin
4. epidermal growth and collagen synthesis leads to a strong collagenous join
5. epidermis grows over top
86
Why is a scar initially red? What colour does it turn after time has passed?
initially red as there is still blood present in the collagen
eventually turns white (colour of collagen)
87
Describe the process of healing by second intention
1. small blood vessels move in from the edges of the gap
2. fibroblasts enter the site of trauma and make collagen- granulation of tissue
3. fibroblasts organise tissue to form organised collagen fibrils
4. early thrombus scar forms before skin contracts
5. epidermis grows over the top leaving a white scar
88
What is atherosclerosis?
a disease characterised by the formation of atherosclerotic plaques the intima of large and medium sized arteries
it is often asymptomatic
89
What is an atheroma?
focal thickening of the tunica intimal of arteries, produced through the movement of LDLs from the lumen
90
What is an atherosclerotic plaque made up of?
fibrous tissue
lipid component (cholesterol)
lymphocytes
91
Describe the process of atheroma formation
1. endothelial cell dysfunction (e.g. lots of cholesterol damages wall)
2. high density of LDLs in blood begin to accumulate in artery wall
3. macrophages are attracted to site of damage and take up lipid to form foam cells (inflammatory response)
4. formation of fatty streak
5. activated macrophages will release lots of their own products- cytokines and growth factors
6. smooth muscle proliferation to intimal around lipid core and formation of fibrous cap (collagen)
7. plaque may rupture leading to thrombosis and complete occlusion of vessel lumen
92
What kind of systems do you find atherosclerosis in?
high pressure systems - never low pressure
93
What can happen if a thrombus forms on a disrupted atherosclerotic plaque?
cerebral infarct
carotid atheroma, leading to TIA
MI
aortic aneurism
peripheral vascular disease
gangreen
94
What happens in an aortic aneurism ruptures?
sudden death
95
What are the risk factors of atherosclerosis?
hypercholestrolaemia (most important)
smoking
hypertension
diabetes
male sex
increasing age
96
What are the preventative measures for atherosclerosis?
smoking cessation
blood pressure control
weight reduction
low dose aspirin
statins
97
What is the standard drug for reducing cholesterol?
statins
98
What is apoptosis?
programmed cell death
99
What inhibits apoptosis?
growth factors
extracellular cell matrix
sex steroids
100
What induces apoptosis?
glucocorticoids
free radicals
ionising radiation
DNA damage
101
When does apoptosis occur?
in fully differentiated cells
in development
in normal function
in disease processes
102
How is apoptosis mediated?
via capase enzymes
103
Describe the extrinsic pathway of apoptosis.
- Fas ligand binds to Fas receptor on cell surface
- ligand binding results in clustering of receptor molecules on the cell surface and initiation of signal transduction cascade
- capases are activated which triggers apoptosis
104
What are the 2 types of Fas receptor?
TNFR1
CD95
105
What is the extrinsic pathway for apoptosis used for?
used by immune system to eliminate lymphocytes
106
Describe the intrinsic pathway of apoptosis
- involves inducers and inhibitors
- inducer or p53 gene acts on Bax receptor inside cell which activates capase enzymes and stimulates apoptosis
- inhibitors act on Bcl-2 receptor inside cell and inhibit capase enzymes which inhibits apoptosis
107
What does the Bcl-2:Bax ratio of a cell determine?
the cell's susceptibility to apoptotic stimuli
108
What is necrosis?
traumatic cell death which induces inflammation and repair
characterised by bioenergetic failure and loss of plasma membrane integrity
109
What is coagulative necrosis?
- most common type
- can occur in most organs
- caused by ischaemia
110
What is liquefactive necrosis?
occurs in brain due to its lack of substantial supporting stroma
111
What is caseous necrosis?
- causes a "cheese" pattern
- TB is characterised by this form of necrosis
112
What is gangrene?
necrosis with rotting of the tissue
113
Why does gangrene appear black?
affected tissue appears black due to deposition of iron sulphide from degraded haemoglobin
114
What is genetic disease?
disease that occurs primarily from a genetic abnormality
115
What is congenital disease?
disease that has symptoms present at birth
116
What is inherited disease?
disease caused by an inherited genetic abnormality, may not manifest itself until later in life
117
What is acquired disease?
caused by non-genetic environmental factors usually occurring after birth
118
Give an example of a disease which is both acquired and congenital.
fetal alcohol syndrome
119
Define hypertrophy
increase in tissue size due to increase in size of constituent cells
120
Give examples of hypertrophy
- muscle hypertrophy in body builders
- uterine hypertrophy in pregnancy
- cardiac muscle hypertrophy due to hypertension
121
Define hyperplasia
increase in tissue size due to increase in number of constituent cells
122
What cells are susceptible to hyperplasia?
any cells that can divide, i.e. not myocytes or neurones
123
Give an example of hyperplasia
hyperplasia in bone marrow cells in those living at high altitudes
124
Define atrophy
decrease in tissue size caused by either decrease in number of constituent cells or a decrease in their size
125
Which organs are most susceptible to atrophy?
skeletal muscle
cardiac muscle
secondary sex organs
brain
126
Give examples of atrophy
- thymus after puberty
- skeletal muscle atrophy after disuse
127
Define metaplasia
the change in differentiation of a cell from one fully-differentiated cell type to another
128
What causes metaplasia?
alterations in cellular environment
thought to be caused by stem cell reprogramming
129
Is metaplasia reversible?
yes
130
Give an example of metaplasia
Barrett's oesophagus- squamous epithelium of oesophagus becomes columnar due to exposure to stomach acid
131
What happens if metaplasia persists?
it can progress to dysplasia and eventually carcinoma
132
What happens is Barrett's oesophagus persists?
metaplasia becomes dysplasia and progresses to adenocarcinoma
133
Define dysplasia
morphological changes seen in cells in the progression to becoming cancer
134
What type of epithelium is prone to dysplasia?
cervical
respiratory
135
Define carcinogenesis
the transformation of normal cells to neoplastic cells via permanent genetic alterations or mutations
136
Define carcinogenic
cancer causing
137
Define oncogenic
tumour causing
138
Define tumour
any abnormal swelling
139
Define neoplasm
an abnormal mass of tissue that forms when cells grow and divide more than they should/ not die when they should
can be benign or malignant
140
Define oncogenesis
process by which normal cells transform into benign neoplasms
141
What percentage of cancers are environmental vs genetic?
85% environmental
15% genetic
142
Define carcinogen
mutagenic agent known to cause cancer
143
List the DNA viral carcinogens and the cancer that they cause
Human Herpes Virus (HHV8) - Kaposi sarcoma
Epstein Barr Virus (EBV) - Burkitt lymphoma, nasopharyngeal carcinoma
Hep B - Hepatocellular carcinoma
Human Papillomavirus (HPV) - squamous cell carcinomas of the cervix, penis, anus, head and neck
Merkle cell polyomavirus (MCV) - merkle cell carcinoma
144
List the RNA viral carcinogens and the cancer that they cause
Human T-lymphotrophic virus (HTLV-1) - adult T-cell leukaemia
Hep C - hepatocellular carcinoma
145
Where does Kaposi sarcoma affect?
GI tract
146
What cancer is caused by polycyclic aromatic hydrocarbons?
lung cancer
skin cancer
147
What cancer is caused by aromatic amines?
bladder cancer
148
What cancer is caused by nitrosamines?
gut cancer
149
What cancer is caused by alkylating agents?
leukaemia
150
Which non ionising radiation causes cancer? What types of cancer does it cause?
increased exposure to UVA or UVB
causes basal cell carcinoma
squamous cell carcinoma
melanoma
151
How does UV radiation cause cancer?
causes DNA strand to break down and DNA mutations occur
152
Which patients are more susceptible to cancer caused by UV radiation?
patients with xeroderma pigmentosum (extreme sun sensitivity)
153
What cancer are radiographers susceptible to?
skin cancer
154
What cancer are uranium miner susceptible to?
lung cancer
155
What sort of cancer does granite bedrock cause and why?
lung cancer
uranium decays to radon which is ionising radiation
156
What cancer is prevalent in Ukrainian children and why?
thyroid cancer
Chernobyl disaster
157
What cancer is caused by increased exposure to oestrogen?
mammary (breast) cancer
endometrial cancer
158
What cancer is caused by anabolic steroids?
hepatocellular cancer
159
What cancer is caused by aflatoxin B1?
hepatocellular carcinoma
160
What is aflatoxin B1 and how is it produced?
mycotoxin
released by fungus aspergillus
161
Name a carcinogenic parasite and the cancer it causes
shistoma
bladder cancer
162
What type of cancer is caused by asbestos?
mesothelioma (pleural cancer)
163
What type of cancer does arsenic cause?
bladder
skin
164
What is classification of a tumour based on?
behaviour and histogenesis
165
What is histogenesis?
formation of different tissues from undifferentiated cells
166
What are the 2 types of neoplasia?
benign
malignant
167
Describe the differences between benign and malignant neoplasms.
1. INVASION: Benign do not invade basement membrane, malignant does
2. DIRECTION OF GROWTH: benign are exophytic (grow outwards), malignant of endophytic (grow inwards)
3. RATE OF GROWTH: benign have low mitotic activity (slow growing), malignant have high mitotic activity (fast growing)
4. CIRCUMSCRIBED: benign are circumscribed, malignant are poorly circumscribed
5. NECROSIS: necrosis and ulceration rare for benign, common for malignant
168
Why do malignant neoplasms cause necrosis but benign neoplasms do not?
malignant neoplasms grow too fast to grow an adequate blood supply hence tissue dies, benign neoplasms grow much slower
169
What are the long term effects of benign neoplasms?
- pressure on adjacent tissues
- obstruction of ducts/ hollow organs
- produce hormones
- can be pre-malignant (can become cancerous)
170
What are the components of a neoplasm?
neoplastic cells
stroma
171
Give the features of neoplastic cells
- always derived from nucleated cells
- usually monoclonal
- growth pattern related to parent cell
- synthetic activity related to parent cells (collagen, hormone secretion, etc)
172
What is the stroma of a neoplasm?
connective tissue framework providing mechanical and nutritional support
173
What cancer is the exception to the usual structure of a neoplasm?
leukaemia/ blood cancer- no stroma
174
What promotes blood vessel growth in neoplasms?
VEGF
fibroblast growth factors
175
What is angiogenesis?
formation of new blood vessels
176
What is classification of a neoplasm based on?
behaviour
histogenesis
177
What are the behaviour categories of a neoplasm?
benign
borderline
malignant
178
What are the component of histogenesis of a neoplasm?
specific cell/ origin of tumour
histological grading
179
Give 4 possible neoplasm origins
epithelial
connective tissue
lymphoid
haemopoetic
180
What is histological grade of a neoplasm based on? Describe the grading system.
based on extent to which the tumour resembles it's original histology
grade 1: well-differentiated (most closely resembles parent tissue)
grade 2: moderately differentiated
grade 3: poorly differentiated
181
What does suffix -oma imply?
any neoplasm
182
Describe types of benign and malignant epithelial tumours.
BENIGN:
papilloma- benign tumour of non glandular tissue
adenoma- benign tumour of secretory tissue
MALIGNANT:
carcinoma- malignant tumour of epithelial cells
adenocarcinoma- malignant tumour of glandular epithelium
183
What is a lipoma?
benign
connective tissue tumour
of adipocytes
184
What is rhabdomyoma?
benign
connective tissue tumour
of striated muscle
185
What is leiomyoma?
benign
connective tissue tumour
of smooth muscle
186
What is angioma?
benign
connective tissue tumour
of vascular system
187
What is chondroma?
benign
connective tissue tumour
of cartilage
188
What is osteoma?
benign
connective tissue tumour
of bone
189
What is neuroma?
benign
connective tissue tumour
of nerves
190
What is liposarcoma?
malignant
connective tissue tumour
of adipocytes
191
What is rhabdomyosarcoma?
malignant
connective tissue tumour
of striated muscle
192
What is leiomyosarcoma
malignant
connective tissue tumour
of smooth muscle
193
What is Chondrosarcoma?
malignant
connective tissue tumour
of cartilage
194
What is osteosarcoma?
malignant
connective tissue tumour
of bone
195
What is angiosarcoma?
malignant
connective tissue tumour
of vascular system
196
What is neurosarcoma?
malignant
connective tissue tumour
of nerves
197
Define anaplastic
a tumour in which the cell-type of origin is unknown, so tumour origin is said to be anaplastic
198
What is granuloma?
a type of inflammation
199
What is a mycetoma?
NOT A NEOPLASM
ball of fungus in lung cavity
200
What is a tuberculoma?
NOT A NEOPLASM
inflammation due to TB
201
What is melanoma?
malignant neoplasm (exception to nomenclature)
of melanocytes
202
What is mesothelioma?
malignant neoplasm (exception to nomenclature)
of mesothelial cells
203
What is lymphoma?
malignant neoplasm (exception to nomenclature)
of lymphoid cells
204
What is blastoma?
embryological malignant neoplasm
205
Define neoplasm "in situ"
when the neoplasm has proliferated but has not broken through the basement membrane to other tissues
206
What type of neoplasms can you say are "in situ"?
epithelial neoplasms only
207
Define metastasis
the process whereby malignant tumours spread from their site of origin to form other tumours at distant sites
208
What is the type of malignant neoplasm that does not metastasise?
basal cell carcinomas never metastasise
209
Describe the process of metastasis
1. detachment of tumour cells from their neighbours
2. invasion of surrounding connective tissue to reach conduits of metastases
3. intravasation into the lumen of vessels
4. evasion of host defence mechanisms, such as NK cells
5. adherence to endothelium at a remote location
6. extravasation of the cells from the vessel lumen to the surrounding tissues
7. tumour cells proliferate in the new environment
210
What route of metastasis does carcinomas and sarcomas usually take?
carcinoma- lymphatic spread
sarcoma- haematogenous spread
211
What is the most common metastasis?
metastasis from lymphatic system
212
Give 5 ways in which metastasis physically occurs?
via blood vessels (haematogeneous)
via lymphatics
across body cavities (transcoelomic)
along nerves
direct implantation during surgery
213
Describe the process of metastasis to the lung
1. If carcinoma enters venous system, it will travel through the blood vessels to the vena cavae, right atrium, right ventricle and onto pulmonary circultion
2. From there, as the lung blood vessels act as a sieve, it will get stuck at some point
3. If this new neoplasm site then grows into venous system of the pulmonary circulation, it can travel anywhere in the body
214
Describe the process of metastasis to the liver
1. liver receives 100% of blood from colorectal
2. neoplasm may break off from digestive system and travel in the blood stream to the liver through the portal venous system
3. liver blood vessels act as sieve as they go down to capillary level
4. neoplasm imbeds at some point in vasculature tree
215
When is cancer considered to be invasive?
when it has breached its own tissue type into another area
216
What is the name for a metastatic tumour that has only JUST broken through the basement membrane?
micro-invasive carcinoma
217
What is invasion of cancer dependant on?
decreased cellular adhesion
increased cellular motility
production of lytic enzymes to break down surrounding tissues
218
What is tumour staging?
the extent of tumour spread determined by histopathological examination and clinical examination
