general pathology Flashcards

1
Q

hospital autopsies

A

<10% of autopsies in the UK

Requires Medical Certificate cause of Death (MCCD)

Audit, teaching, governance, research

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2
Q

medico-legal autopsies

A

> 90% of autopsies in the UK

Coronial

forensic

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3
Q

presumed natural death

A

Cause of death not known

not seen by doctor within days of death

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4
Q

presumed iatrogenic deaths

A

peri/post operative deaths

anaesthetic deaths

abortion

complications of therapy

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5
Q

presumed unnatural deaths

A

accidents

custody deaths

war/industrial pensions

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6
Q

doctor referral for autopsy

A

No statutory duty to refer

common law duty

GMC guidance

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7
Q

registrar of BDM referral for autopsy

A

statutory duty to refer

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8
Q

other referrals for autopsy

A

Relatives

the police

anatomical pathology technicians

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9
Q

histopathologists

A

Hospital autopsies

coronial autopsies
(Natural deaths, drowning, suicide, accidents, road traffic deaths, fire deaths, industrial deaths, peri/post operative deaths)
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10
Q

forensic pathologists

A
Coronial autopsies
(homicide, death in custody, neglect and any done by histopathologists due to the action of a third party)
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11
Q

inflammation

A

local and physiological response to tissue injury

not a disease but a manifestation of disease

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12
Q

outcomes and harmful effects of inflammation

A

Benefits=
resolution
suppuration
organisation

Diseases=
Digestion of normal tissue
Swelling
Compressing brain tissue
Fibrosis from chronic inflammation 
Autoimmunity
Over reaction to stimulus
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13
Q

acute inflammation

A

initial and often transient series of tissue reactions to injury

sudden onset

short duration

usually resolves

cell type= neutrophil polymorphs

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14
Q

chronic inflammation

A

Subsequent of often prolonged tissue reactions following the initial response

slow onset or sequel to acute

long duration

may never resolve

cell type= macrophages

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15
Q

cells involved in inflammation

A
neutrophil polymorphs
macrophages
lymphocytes
endothelial cells
fibroblasts
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16
Q

neutrophil polymorphs (inflammation)

A

short lived

first on the scene of acute

cytoplasmic granules full of enzymes that kill bacteria

usually die at the scene of inflammation

release chemicals that attract other inflammatory cells such as macrophages

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17
Q

macrophages (inflammation)

A

long lived cells- weeks to months

phagocytic properties

ingest bacteria and debris

carry debris away

present antigens to lymphocytes

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18
Q

lymphocytes (inflammation)

A

long lived cells- years

produce chemicals that attract other inflammatory cells

immunological memory

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19
Q

endothelial cells (inflammation)

A

line capillaries

become sticky in areas of inflammation so inflammatory cells adhere to them

become porous to allow inflammatory cells to pass into tissues

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20
Q

fibroblasts (inflammation)

A

long lived cells

form collagen in areas of chronic inflammation

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21
Q

causes of acute inflammation

A

microbial infections (bacterial, viruses)

hypersensitivity (parasites, allergic reactions)

physical agents (trauma, ionising radiation, heat)

chemicals (corrosives, acids, alkalis)

bacterial toxins

tissue necrosis

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22
Q

microbial infections (inflammation)

A

most common cause of acute inflammation

viruses lead to death of cells by intracellular multiplication

bacteria release exotoxins

parasitic infections and TB inflammation are examples of where hypersensitivity is important

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23
Q

hypersensitivity inflammation

A

altered state of immunological responsiveness causes inappropriate or excessive immune reaction

damages tissues

has cellular or chemical mediators

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24
Q

physical agents in inflammation

A

tissue damage leading to inflammation may occur through physical trauma, UV or other ionising radiation, burns or frostbite

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25
chemicals in inflammation
corrosive chemicals provoke inflammation through gross tissue damage infecting agents may release specific chemical irritants that lead directly to inflammation
26
tissue necrosis (inflammation)
death of tissues to due lack of oxygen or nutrients usually from inadequate blood flow acute inflammatory response due to peptides released from dead tissue
27
macroscopic appearance of inflammation
Top Cars Require Driving Licences Tumor, Calor, Rubor, Dolor, Loss of function Some Hoes Read Porn Lots Swelling, Heat, Red, Pain, Loss of function
28
Rubor
Redness acutely inflamed tissue appears red caused by dilation of small blood vessels in damaged area
29
Calor
Heat only in peripheral parts of the body- skin caused by increased blood flow- hyperaemia vascular dilation to deliver blood to area systemic fever from chemical mediators, contributes
30
tumor
Swelling oedema- accumulation of fluid in extravascular space as part of fluid exudate physical mass of inflammatory cells migrating into the area formation of connective tissue
31
dolor
Pain partly stretching of tissues due to oedema and pus under pressure in abscess cavity chemical mediators- bradykinin and prostaglandins and serotonin- induce pain
32
loss of function
movement of inflamed area is consciously and reflexly inhibited by pain severe swelling may immobilise tissues
33
Acute inflammation response has 3 processes
changes in vessel diameter and flow increased vascular permeability and formation of the fluid exudate formation of the cellular exudate- emigration of neutrophil polymorphs into extravascular space
34
stages in neutrophil polymorph emigration (inflammation)
margination of neutrophils pavementing of neutrophils pass between endothelial cells pass through basal lamina and migrate into adventitia
35
endogenous chemical mediators cause: | inflammation
vasodilation emigration of neutrophils chemotaxis increased vascular permeability itching and pain
36
chemical mediators released from cells | inflammation
histamine lysosomal compounds chemokines
37
plasma factors | inflammation
enzymatic cascade systems, which are unrelated and produce various inflammatory mediators
38
systemic effects of inflammation
pyrexia constitutional symptoms weight loss amyloidosis
39
causes of chronic inflammation
transplant rejection progression from acute primary chronic recurrent episodes of acute
40
macroscopic appearance of chronic inflammation
chronic ulcer chronic abscess cavity thickening of the wall of a hollow viscus granulomatous inflammation fibrosis
41
microscopic features of chronic inflammation
The cellular infiltrate consists characteristically of lymphocytes plasma cells and macrophages A few eosinophil polymorphs may be present, but neutrophil polymorphs are scarce Some of the macrophages may form multinucleate giant cells There may be evidence of continuing destruction of tissue at the same time as tissue regeneration and repair Tissue necrosis may be a prominent feature, especially in granulomatous conditions such as tuberculosis
42
granulomas
aggregate of epitheliod histiocytes (activated macrophages) may contain other cells such as lymphocytes and histiocytic giant cells granulomatous inflammation is a specific type- such as tuberculosis and leprosy
43
epitheliod histiocytes
resemble epithelial cells activated macrophages arranged in clusters little phagocytic activity but adapted to secretory function
44
appearance of granulomas
may be augmented by presence of caseous necrosis or by conversion of some of the histiocytes into multinucleate giant cells
45
histiocytic giant cells
form where particulate matter, that is indigestible by macrophages, accumulates form when foreign particles are too large to be ingested by just one macrophage multinucleate giant cells w/ 100+ nuclei little phagocytic activity
46
types of histiocytic multinucleate cells
langhans giant cells- horse shoe arrangement of peripheral nuclei at one pole foreign body giant cells- large with nuclei randomly scattered throughout touton giant cells- central ring of nuclei, peripheral to which there is lipid material
47
treating inflammation
aspirin ibuprofen- inhibit prostaglandin synthase steroids- bind to DNA up regulate inhibitors of inflammation and down regulate chemical mediators of inflammation
48
regeneration/resolution
initiating factor is removed tissue is undamaged or able to regenerate
49
examples of regeneration
liver after surgery to remove a lobe lobar pneumonia- pneumocytes can regenerate skin abrasions skin wounds- healing by first intention
50
repair
initiating factor is still present tissue is damaged and unable to regenerate replacement of damaged tissue by fibrous tissue collagen produced by fibroblasts brain fibrosis= gliosis
51
examples of repair
heart after myocardial infarction brain after cerebral infarction liver cirrhosis skin wounds- healing by second intention
52
cells that regenerate
``` hepatocytes pneumocytes blood cells gut epithelium skin epithelium osteocytes ```
53
cells that dont regenerate
myocardial cells | neurones
54
regeneration example
healing by first intention- ``` sutured edge to edge two edges fill gap with blood and fibrin epidermis regrows fibroblasts form collagen scar forms, stronger than normal skin ```
55
repair example
healing by seconds intention large amount of tissue loss- normally trauma can't be sutured together gap present so no epithelial cells to regenerate gap filled by capillaries and collaged until two edges can grow large scar formed
56
Ways our healthy body prevents thrombosis occurring spontaneously
Laminar flow- cells travel in the centre of arterial vessels and don't touch the side endothelial are not sticky when they are healthy
57
thrombosis definition
the formation of a solid mass from blood constituents in an intact vessel of a living person
58
formation of a thrombus
platelet aggregation platelets release chemicals when they aggregate causing them to start the cascade of clotting proteins in the blood both of these reactions involve positive feedback loops; therefore difficult to stop once clotting cascade has started there is a formation of insoluble fibrin
59
causes of thrombosis
change in vessel wall change in blood flow change in blood constituents usually a combination of two or three
60
drugs preventing thrombosis
aspirin heparin warfarin
61
embolus definition
mass of material in the vascular system able to become lodged within a vessel and block it formed when a solid mass in the blood is carried through the circulatory system to a place where it gets stuck and blocks it
62
cause of embolism
thrombus air other- cholesterol crystals, tumours, amniotic fluid, fat
63
embolism location
in venous system then- vena cava -> right side of heart -> lodge in pulmonary arteries (location depends on size) -> can lodge as lungs split into capillaries (lungs act as a filter for venous emboli in arterial system it can travel anywhere downstream
64
ischaemia
reduction in blood blow to a tissue without any other implications inadequate blood supply
65
infarction
reduction in blood flow to a tissue with subsequent local cell death macroscopic event usually caused by thrombus blockage
66
atheroma
aka atherosclerosis pathology of arteries when there is deposition of lipids in the arterial wall with surrounding fibrosis and chronic inflammation the plaques can enlarge to occlude the lumen of vessels endothelium overlying a plaque may rupture and initiate thrombosis within the vessel plaques are predominant cause of myocardial or cerebral infarction
67
plaques contain:
fibrous tissue lipids- cholesterol lymphocytes
68
atherosclerosis distribution in arteries
never low pressure systems- pulmonary arteries high pressure systems=common e.g. aorta
69
epidemiology of atherosclerosis
increases with age more common in lower socioeconomic populations due to risk factors
70
risk factors of atherosclerosis
raised serum lipids- hyper lipidaemia hypertension diabetes mellitus cigarette smoking
71
endothelial damage theory
 Any factor that causes endothelial damage in arteries will lead eventually, by repeated small amounts of damage, to the formation of atherosclerotic plaques  The major process after endothelial damage is chronic inflammation with macrophages and fibroblasts  The lipids within plaques probably derive from the breakdown of inflammatory cells in the plaque  Understanding pathogenesis of atheroma enables prevention or to stop progression
72
atherosclerosis formation
endothelial cells dysfunction- cholesterol damages wall high levels of LDL begins to accumulate in arterial wall macrophages attracted to site of damage and take up lipid to form foam cells- inflammatory response formation of a fatty streak= earliest stage of a plaque activated macrophages release their own products- cytokines and growth factors smooth muscle proliferation around lipid core and formation of a fibrous cap of collagen
73
complications of atherosclerosis
cerebral infarction carotid atheroma- emboli causing transient ischemic attacks myocardial infarction aortic aneurysms peripheral vascular disease gangrene
74
prevention of atherosclerosis
reduce lipids- reduces epithelial damage reduce BP- reduces epithelial damage stop smoking- reduces epithelia damage low dose aspirin reduces platelet aggregation at site of damage
75
apoptosis definition
programmed cell death of a single cell
76
necrosis definition
unprogrammed death of a large number of cells due to an adverse event
77
apoptosis uses
turnover of cells- stem cells divide to produce new cells which mature and differentiate and eventually die by the process of apoptosis embryogenesis- apoptosis removes cells no longer needed as organs develop DNA damage- cells can detect DNA damage (p53 protein)
78
initiation and control of apoptosis
apoptosis is implemented by caspases and Bcl2 protein decision as to whether a cell should activate this process or not is less well understood alternatives to apoptosis can be used cells with a lot of DNA damage prefer apoptosis abnormal apoptosis can occur in a variety of situations including drugs, graft versus host disease and neurodegeneration p53 is involved in detection of DNA damage breakdown in control of apoptosis can cause Cancer (lack of) or HIV (too much)
79
necrosis
catastrophic event that physically causes death of a large number of cells and resolved or is repaired by basic inflammatory processes
80
examples of necrosis
``` infarction burn frostbite toxic spider venom avascular necrosis of bone pancreatitis ```
81
types of necrosis
coagulative necrosis- sticks together liquefactive necrosis- liquid caseous necrosis- resembles soft cheese e.g. TB
82
genetic disease
one that occurs primarily from a genetic abnormality some diseases that are pure genetic diseases
83
inherited diseases
caused by inherited genetic abnormality may not manifest until later in life
84
types of inherited disease
chromosome abnormalities e.g. Down syndrome Mendelian inheritance e.g. single gene disorders
85
single gene disorder
abnormality of a single gene causes the disease dominant or recessive
86
dominant definition
will be present where there is only one copy of the abnormal gene e.g. Huntington's
87
Recessive definition
only expressed if both copies of the gene are abnormal e.g. cystic fibrosis
88
co-dominant definition
both alleles are expressed e.g. AB blood group
89
autosomal definition
occurring on the non-sex chromosomes
90
sex-linked definition
occurs on the sex chromosomes regions which dont have a corresponding region on the opposing chromosome mostly x-linked as men only have one Y and women have none more common in males as they only have one X
91
polygenic inheritance
interaction of several genes usually on different chromosomes e.g. breast cancer many diseases have strong genetic component still need the appropriate environment to be expressed as disease
92
congenital diseases
present at birth | mostly genetic but can be acquired- rhesus haemolytic disease or foetal alcohol syndrome
93
acquired diseases
disease or condition developed after birth caused by non-genetic environmental factors but may have strong genetic background
94
disorders of development
neural tube defect cleft palate spina bifida ventricular septal defect
95
disorders of growth
GH deficiency GH excess mutation in the COL2A1- type II collagen mutation in fibroblast growth factor receptor 3 gene
96
hypertrophy
increase in size of tissue caused by an INCREASE IN SIZE of cells without an increase in number
97
physiological uses of hypertrophy
skeletal muscle cells exposed to an increased workload cannot divide and respond by hypertrophing
98
pathological hypertrophy
myocardium undergoes hypertrophy with high BP
99
hyperplasia
increased growth caused by an INCREASE IN NUMBER of cells can be accompanies by increase of cell size
100
physiological use of hyperplasia
during pregnancy and lactation, breast epithelial cells respond to increase in demands by increasing in number
101
pathological hyperplasia
prostate undergoes hyperplasia with age in response to excess of oestrogen stimulation
102
atrophy
decrease in size of tissue caused by DECREASE IN NUMBER of constituent cells or by DECREASE IN THEIR SIZE
103
physiological use of atrophy
various embryological structures undergo atrophy during foetal life thymus atrophies in early adult life
104
pathological atrophy
occurs as a result of loss of blood supply, loss of innervation, loss of pressure, lack of nutrition, lack of or result of hormonal stimulation
105
metaplasia
reversible transformation of one mature cell type into another fully differentiated cell type adaptive response to injurious stimuli e.g. transformation of normal pseudostratified columnar epithelium of bronchi intro squamous epithelium following repeated exposure to cigarette smoke
106
dysplasia
premalignant condition characterised by increased growth, cellular atypia and decreased differentiation imprecise term for morphological changes seen in cells in progression into cancer
107
ageing
progressive loss of various functions and accumulation of diseases
108
mechanisms of ageing
many organs do not have cells that regenerate so if they die there will be a loss of function in that organ acquired cancers may occur because of accumulated DNA damage over a lifetime of cell divisions
109
manifestations of ageing
development of acquired cancers neurodegeneration- dementia, parkinsons dermal elastosis osteoporosis osteoarthritis vision loss deafness- loss of hair cells reduced immunity
110
cancer
generic term for malignant tumour
111
metastasis
the development of secondary malignant growths at a distance from a primary site of cancer
112
metastatic tumours
arise from cells that naturally move around the body- lymphocytes tumours from these cells will never stay in one site so the treatment for these must always be for the whole body
113
non- metastatic tumour
only spread locally and do not metastasise to other regions tumours can be treated by local excision
114
mixture of non-metastatic and metastatic
most common tumours e.g. breast cancer tumour staging is important if it hasnt spread it can be excised but if it has spread then it requires excision and systemic treatment
115
useful cancer treating facts
basal cell carcinoma of the skin invades locally- so can be locally excised carcinomas spread to lymph nodes that drain the primary site and so can spread through the blood to bone most common carcinomas to do so are breast, prostate, lung, thyroid and kidney
116
carcinogenesis
the transformation of normal cells to neoplastic cells through permanent genetic alterations or mutations applies only to malignant tumours
117
carcinogens
agents known or suspected to cause cancer
118
oncogens
cause tumours
119
environmental agents and cancer
account for 85% of cancer risk factors ``` chemical viruses radiation biological agents (hormones, parasites, mycotoxins) miscellaneous ```
120
host factors and cancer
``` race diet age gender premalignant lesions transplacental exposure ```
121
chemicals and cancer
no common structural features some act directly most require metabolic conversion from pro-carcinogens to ultimate carcinogens
122
radiant energy and cancer
ionising radiation long term effect skin cancer and sunlight lung cancer in uranium miners
123
biological agents and cancer
hormones- oestrogen increases risk of mammary cancer mycotoxins- aflatoxin B2= hepatocellular carcinoma parasites- shistosoma= bladder cancer
124
miscellaneous carcinogens
asbestos
125
conventional chemotherapy mechanism of action
vinblastine= antimicrotubule agent- prevents anaphase etoposide= prevents topoisomerase II- prevents DNA replication cisplatin and ifosamide= bind directly to DNA- inhibits DNA synthesis by cross linking
126
Conventional chemotherapy issues
not selective for tumour cells usually affects normal cells that also divide fast- myelosuppression, hair loss, diarrhoea not good treatment for slow dividing tumours
127
conventional chemotherapy tumours
fast dividing tumours germ cell tumours of testis acute leukaemias lymphomas embryonal paediatric tumours
128
targeted chemotherapy
more effective with fewer side effects recognises differences between normal cells and cancer cells
129
detecting differences between normal and cancer cells
gene arrays- different expression of genes (overexpression of growth factor receptor due to mutation in this gene) proteomics- different proteins tissue microarrays
130
Cetuximab (Erbitux)
monoclonal antibody against epidermal growth factor receptor chimeric IgG humanised monoclonal antibody, binds competitively to extracellular domain of EGFR, antitumour activity in xenograft models, blocks production of VEGF, interleukin 8 and bFGF
131
programmed cell death protein I
immune checkpoint inhibits t cell response prevents auto-immunity in normal physiology
132
treating breast cancer using oestrogen receptors
epithelial cells respond to oestrogen as a growth factor, giving a drug that blocks oestrogen receptors on the cancer cells should inhibit their growth only effective if the breast cancer has oestrogen receptors on the surface of its cells
133
treating breast cancer using HER2 protein
some tumours overexpress a growth factor on the cell surface (HER2 protein) (coded for by (HER2 gene) 20% of breast cancer have amplified number of copies of this gene use herceptin and lapatinib
134
neoplasm
a lesion resulting from the autonomous or relatively autonomous abnormal growth of cells which persists after the initiating stimulus has been removed ``` Neoplasia is: o Autonomous o Abnormal o Persistent o New growth ```
135
neoplasm and tumour difference
tumour is any abnormal swelling, including: neoplasm, inflammation, hypertrophy, hyperplasia
136
neoplastic cells
derive from nucleated cells usually monoclonal growth pattern related to parent cell synthetic activity related to parent cell (collagen, keratin, hormones etc. )
137
tumour angiogenesis
benign neoplasms are slow growing therefore dont outgrow blood supply malignant neoplasms are fast growing so outgrow blood supply- forms central necrosis
138
classification of neoplasms
classification occurs to determine treatment and prognosis methods of classification= behavioural (benign/malignant) histogenetic (cell of origin)
139
behavioural classification
classified as benign, borderline, malignant Borderline tumours defy precise classification
140
benign neoplasms
- localised, non-invasive - slow growth rate - low mitotic activity - close resemblance to normal tissue - circumscribed or encapsulate - nuclear morphometry often normal - necrosis and ulceration are rare
141
morbidity and mortality of benign neoplasm
``` pressure on adjacent structures obstruct flow produce hormone transform into malignant anxiety ```
142
malignant neoplasm
- invasive - metastasise - rapid growth - variable resemblance to normal tissue - poorly defined or irregular border - hyperchromatic and pleomorphic nuclei - increased mitotic activity - necrosis and ulceration= common - encroach upon and dectroy surrounding tissue - have 'crab like' cut surface (cancer= latin for crab)
143
morbidity and mortality of malignant neoplasms
``` destruction of adjacent tissue metastases blood loss from ulcers obstruction of flow hormone production anxiety and pain ```
144
histogenetic classification
histogenesis= specific cell of origin of tumour
145
nomenclature of neoplasia
have suffix -oma | prefix defends on behavioural and histogenesis
146
benign epithelial neoplasms
papillomas: - benign tumour of non-glandular, non secretory epithelium - prefix with cell type of origin, e.g. squamous cell papilloma adenomas: - benign tumour of glandular or secretory epithelium - prefix with cell type of origin e.g. colonic adenoma
147
malignant epithelial neoplasms
carcinomas: - malignant tumour of epithelial cells - prefixed with cell type e.g. transitional cell carcinoma adenocarcinomas: - carcinomas of glandular epithelium e. g. adenocarinoma of colon
148
benign connective tissue neoplasms
prefix of cell of origin - lipoma=adipocytes - chondroma=cartilage - osteoma=bone - angioma=vascular - rhabdomyoma=striated muscle - leimyoma=smooth muscle
149
malignant connective tissue neoplasms
- liposarcoma=adipose tissue - chondrosarcoma=cartilage - osteosarcoma=bone - angiosarcoma=blood vessels - rhabdomyosarcoma=striated muscle - leiomyosarcoma=smooth muscle
150
further malignant classification
anaplastic= cell type of origin is unknown carcinomas and sarcomas are further classified according to degree of differentiation (low grade is more differentiated)
151
exceptions to neoplasm classification
- not all omas are neoplasms (granuloma= inflammation) - not all malignant tumours are carcinoma or sarcoma (melanoma= malignant melanocytes, lymphoma=malignant lymphoid cells) - some tumours are named after people (burkitt's lymphoma, kaposi's sarcoma, grawitz tumour)
152
in situ neoplasia
applies only to epithelia neoplasms the lesion has the cytological features of a malignant neoplasms may progress to invasive disease screening may allow detection and treatment of the disease before the development of carcinoma
153
invasion of neoplasia
defining feature of a malignant neoplasm enables neoplastic cells to spread directly through tissues and gain access to blood vessels and lymphatic channels dependent upon- decreased cellular adhesion, abnormal cellular motility, production of enzymes with a lytic effect on the surrounding tissues
154
metastasis
process by which a malignant tumour spreads from its primary site to produce secondary tumours at distant sites may occur via blood vessels (haematogenous), lymphatics, across body cavities (transcoelomic), along nerves or as a result of direct implantation during surgery (iatrogenic)
155
metastasis cascade
detachment invasion intravasation evasion of host defences arrest extravasation vascularisation
156
mechanism for neoplasia invasion of basement membrane
invasion of a basement membrane then invasion of extracellular matrix proteases- matrix metalloproteinases (collagenase, cathepsin D, urokinase-type plasminogen activator) cell motility
157
tumour cell motility
tumour cell derived motility factors breakdown products of extracellular matrix
158
intravasation of neoplasm
collagenases cell motility
159
neoplasm evasion of host immune defence
aggregation with platelets shedding of surface antigens adhesion to other tumour cells
160
extravasation of neoplasm
adhesion receptors collagenases cell motility
161
growth at metastatic site
growth factors tend to be autocrine, positive feedback
162
angiogenesis of new metastases
angiogenesis promoters- vascular endothelial growth factors, basic fibroblast growth factor angiogenesis inhibitors- angiostatin, endostatin, vasculostatin
163
Routes of metastasis (lungs)
tumours invade veins and lymphatics as arteries have thick walls, so tumours travel to lungs via right side of heart sarcomas and any common (non-colonic) cancers tend to metastasise in the lung
164
Routes of metastasis (Liver)
tumours from colon travel via portal vein to liver where the capillaries act as a filter colon, stomach, pancreas, carcinoid tumours of the intestine
165
Routes of metastasis (Bone)
``` Prostate breast thyroid lung kidney ```