Tumour pathology 1-3 Flashcards
What are the 3 most important rules that a cell must obey?
differentiate - specialised cell
grow when instructed
die when instructed
What can a cell do if its going to grow abnormally?
more or less cells
bigger or smaller cells
different types of cells
What abnormalities indicate disease?
doesn’t differentiate
grows without regulation
doesn’t die when instructed
What does hyperplasia mean?
increase in the no. cells
What does hypertrophy mean?
cells getting bigger, in response to physiological stimulus or pathological
What does atrophy mean?
decrease in the number and or size of cells
physiological
What is epithelium?
lining surface of various different sorts of organs and on surface of skin, oesophagus, gut and making up most of internal organs.
Describe glandular epithelium?
more complicated than squamous epithelium because rather than just cells piled up on top of each other, forms structures like glands and secretes a substance.
Makes up organs with complex functions
What does mucosa mean?
combination of epithelium on surface
and supporting connective tissue beneath epithelium.
What type of tissue does cancer commonly arise from?
epithelial type tissue
What is metaplasia?
changing from one cell type into another cell type
What does a tumour fundamentally mean?
some sort of mass or swelling
What could a tumour be classified into?
benign disorder of cell growth
malignant tumour like cancer
inflammatory swelling - due to trauma
What is neoplasia?
an abnormal growth of tissue
due to uncoordinated proliferation
it persists even after cessation of the stimuli
What are the two categories that neoplasms can be classified into?
benign - CONFINED BY BASEMENT MEMBRANE, don’t grow very quickly, smooth in shape, well differentiated, surgery treatment, low recurrence
malignant- INVASIVE LOCALLY AND DISTANT SPREAD, cells grow pretty rapidly, irregular in shape , poorly differentiated, surgery, radio ,chemo, immunotherapy, high recurrence if not fully removed ,
What is a benign neoplasm?
abnormal growth of cells but does not invade nearby tissue
What is cancer?
a non specific term for a malignant neoplasm
How do we name benign etc..?
First part of cell- about what type of tissue the abnormal cell is trying to differentiate into
e.g. glandular tissue-adeno
squamous- squamous
bone-osteo
rhabdo- skeletal muscle
Suffix tells us if benign or malignant
benign tumour- oma
Examples: adenoma, papilloma, osteoma
How do we name malignant?
adenocarcinoma
carcinoma- malignant and epithelial
adeno- glandular
squamous cell carcinoma
What does the word sarcoma indicate?
connective tissue type malignant neoplasm
What are the exceptions to all ‘oma’ being neoplasia?
granuloma
xanthoma
atheroma
Venn diagram of this to summarise?
not all tumours are neoplasms
neoplasms can be benign or malignant
malignant can be split into what cells are trying to differentiate into
What are oncogenes?
mutations that enable growth of tumour cells
What is the most common tumour found in bone?
osteosarcoma
Give physical characteristics of cancer cells?
-pleomorphic- adopt all different sizes and shapes
-hyperchromatic- can have various shapes and sizes of the nucleus and chromatin much denser. Much denser because more chromosomes due to cells replicating so much- far too much DNA within cell. Form small nuclei within nucleus.
-Highly mitotic (divide rapidly) and abnormal forms
-disorganized structure
Give behaviours of normal epithelial cells
Replicate when required
Stick together and stay put (desmosomes allow them to stick together)
Specialise to a specific role
Die when instructed
Give behaviours of cancer cells?
Unregulated growth
Loss of cohesion (helps them invade e,g, basement membrane damage and invade tissues below)
Immaturity
Immortality
Give all the ways that tumour cells can survive, grow and stay alive?
-avoid immune destruction (they produce programmed death ligand on surface of cell and these attach to immune cells and switch immune system off)
-enable replicative immortality (can replicate forever- to avoid becoming old)
-active invasion and metastasis
-induce angiogenesis- not a native blood supply where the tumour is growing so have to somehow produce growth factors to allow blood vessels to grow new tumours (VEGF)
-resist cell death (switches off BCL 2 )
-deregulate cellular energetics - can survive in environments where there is a lack of oxygen
-sustain proliferative signaling- Constitutive activation of growth factor mechanisms
A lot of oncogenes fall into this category
-evade growth suppressors- evade negative feedback
-possess genome instability and mutation
-mediate a tumor-associated inflammatory response - inflammation associated with angeogenesis and block apoptosis - tumour cells switch that off
Describe angeogenesis?
tumours cannot grow unless they develop their own blood supply
ability to metastasise
if develop a good blood supply to and from tumour then tumours can get into blood cells and get around body- grow at another site
What is necrosis?
premature/ unregulated cell death
passive process
e..g can happen in tumours if outgrow blood supply
What are the different genes involved in carcinogenesis?
proto-oncogene (normal oncogenes within body)
oncogene (mutated proto oncogene )
tumour suppressor - stop cells from dying
How does cancer spread?
Local spread
Lymphatic spread
Haematogenous spread
(able to invade through invade through walls of lymphatic channels or blood vessels and get into circulation of body) - before something triggers adhesion of vessel to organ and then grows and replicates in organ
Trans-coelomic spread- spread across a body cavity
Describe lymphatic spread?
once got through basement membrane and into sub epithelial connective tissue- interact with lymphatic channels
coat lymphatic and disrupt wall of lymphatics and enter lumen of channel and spread through body through lymph nodes
in lymph nodes grow and divide and become lymph node metastatic deposit
Where are common sites for metastatic deposits?
Liver
Lung
Brain
Bone
Adrenal gland
Omentum/peritoneum
Metastatic disposition sites?
Colorectal tumours go to liver often
breast and prostate tumours go to bone
tumours of ovary often involve omentum and peritoneum
Give characteristics of benign tumours?
regular uniform edge where cells are contained within the tumour mass
Give characteristics of malignant tumours?
irregular edge
islands of tumour in surrounding connective tissue
Describe the direct effect of tumours (at the site)?
-could cause pain
-loss of function (motor or sensory) - from compression of nerve signals
-haemorrhage- compressing on blood vessels and eventually leading to disruption and rupture bleeding
Describe local effects of a tumour? (organ wise)
Brain - contained space. Leads to confusion , coma , seizures
Lung- haemoptysis (bleeding into airways and coughing up blood) Dypsnoea (shortness of breath)
Liver- jaundice ( blockage of bile ducts and therefore back up of bllirubin ) disruption to coagulation (lead to bleeding or susceptible to clotting)
Colon- constipation, haemorrhage, diarrhoea
Bone-pain , fracture, anaemia (disrupt bone marrow - which produce red blood cells)
Spine- disruption of spinal cord- parathesia, numbness and possibly paralysis
Describe cachexia (systemic effect of cancer) ?
Weakness/wasting due to chronic illness
Can’t necessarily be fixed by increasing nutrition
Usually muscle loss > fat loss
Describe paraneoplastic syndromes? (systemic effects of cancer)
Some tumours abnormally or inappropriately produce hormones
These hormones have systemic effects
Give examples of hormones secreted by paraneoplastic syndromes?
There are some common associations: many lung cancers lead to these syndromes
ADH (anti-diuretic hormone) will cause the retention of water (and resulting hyponatraemia)
ACTH (adrenocorticotrophic hormone) will cause the adrenal gland to secrete excess cortisol (potentially leading to Cushing syndrome)
PTH (parathyroid hormone) will cause hypercalcaemia
Describe deep vein thrombosis?
Pressing on blood vessel
Describe dysplasia (type of pre cancer)?
Abnormal growth of cells, uncoordinated with normal tissue and continuing even after cessation of stimulus
A disorder of cell growth due to multiple acquired mutations
A form of “pre-cancer” which may transform into a malignant neoplasm with time (and mutations)
A form of “pre-cancer” which may transform into a malignant neoplasm with time (and mutations)
Pre cancer venn diagram?
dysplasia can form a benign tumour
not all benign tumours are dysplastic
-many benign tumours are essentially just uncontrolled growth of normal looking cells
What does dysplasia/ intra epithelial neoplasia mean?
refers to morphological changes within an epithelium due to some sort of stimulus, be that genetic or environmental.
Benign
BUT has potential to be malignant.
Difference between neoplasia and dysplasia?
neoplasia- abnormal growth of cells, un coordinated with normal tissue and continuing even after cessation of stimulus. But cells mature and differentiate very similarly to their normal counterparts.
OPPOSED TO
dysplasia- look different and don’t mature and differentiate as they should do in their normal counterparts.
How is a malignant neoplasm different to a benign neoplasm?
Malignant: has the ability to invade connective tissue and metastasise around the body whereas a benign neoplasm does not
