tumour pathology Flashcards
what is cancer the homeostasis of?
cancer is the homeostasis between cell accumulation by proliferation and cell death, (less cell death, more proliferation)
what is a tumour?
how many cell types are involved within a tumour?
what does “cancer growth is autonomous to themselves” mean?
- a tumour is a neoplasm - “New growth”
- it is usually just one cell type with supporting tissue structures
- Neoplastic cells
- Stroma “normal-like cells” (connective tissue, fibroblasts, blood vessels, immune cells)
- cancer growth is autonomous to themselves, meaning:
- Response to physiological stimuli lost or abnormal, allowing unregulated growth
what is the trend between new number of cases of cancer and age?
number of new cases of cancer increase with age
what are the top 5 most common cancers?
- breast
- prostate
- lung
- bowel
- skin
most common cancers arise from the epithelial component of the organ system
what do neoplastic cells do?
neoplastic cells are not good neighbours, as they affect the tissue locally and distally
- they are disruptive to the environment
what are the 6 hallmarks of cancer?
- evading apoptosis
- self-sufficiency in growth signals (don’t require any help to grow)
- insensitivity to anti-growth signals
- tissue invasion and metastasis
- limitless replicative potential
- sustained angiogenesis
what are 5 characteristics of benign tumours compared to 5 characteristics of malignant tumours
benign:
1. well circumscribed
2. slow growth
3. no necrosis
4. non-invasive
5. no metastasis
malignant:
1. poorly circumscribed
2. rapid growth
3. often necrotic
4. invasive
5. metastasis
describe the clinical relevance of benign tumours?
how do they cause disregulation of the local environments?
- Benign tumour (not always clinically benign)
- Does not invade surrounding structures
- Does not metastasise
- Not always clinically benign as they may (cause disregulation of the local environment):
- have space occupying effects
- Obstruction
- Epilepsy
- Conduction abnormalities
- cause haemorrhage
- Pulmonary
- Gastrointestinal
- affect hormone production
- Pituitary
- Adrenal
- Endocrine pancreas
describe the clinical relevance of malignant tumours?
what are 4 ways a malignant tumour can spread?
- Malignant tumour - secondary growth of cancer cells at a site distant to the original tumour
– Invades
– Metastasises- A colony of malignant cells established at a point distant from the original tumour
1. Directly invade locally (‘cancer the crab’)
2. Via the lymphatics
3. Via the bloodstream (haematological route)
4. Through body cavities (transcoelomic route)
seed and soil:
how do tumours metastasise in different manners?
- Tumour cells don’t all behave the same
-
Not all tumours metastasise in the same manner/with the same distribution: patterns of spread (epithelial derived cancers and where they usually metastasise to)
- Prostate to bone
- Lung to brain, adrenals
- Breast to lung, liver, bone, brain
- Ovary to peritoneal cavity
list and define some names of macroscopic features of cancers:
- sessile (grow more locally)
- polyps (more on surface of a cell layer)
- papillary (gut lining potentially, into the lumen)
- fungating (invades int tissue area where they arised from)
- ulcerating (necrotic damage)
- annular (ring structure within lumen structure or blood vessel)
list some macroscopic features of benign tumours:
macroscopic features of benign tumours:
1. intact surface
2. exophytic growth
3. homogeneous cut surface
4. circumscribed or encapsulated edge
describe 6 microscopic features of each benign and malignant tumours:
microscopic features: benign and malignant
benign:
- Resemble tissue of origin
- Well circumscribed - defined borders
- Well differentiated
- Minimal nuclear pleomorphism - nuclei look normal
- Mitotic figures normal (no cells trying to break into 3 instead of 2)
- No necrosis
malignant:
- Variable resemblance - dont look like tissue
- Poorly circumscribed - no boundaries
- Variable differentiation - dont look like differentiated tissue organ
- Variable pleomorphism may be anaplastic
- Mitotic figures abnormal (tissue trying to break into 3 rather than 2)
- Necrotic
what are cytological features of cells?
describe 5 cytological features of malignancy:
cytological features are nuclear changes seen within the structure and function of and animal cells
- High nucleo-cytoplasmic ratio - high amount of nucleus, lower amount of cytoplasm
- Nuclear hyperchromasia - nucleus appears darker
- Nuclear pleomorphism - nucleus appears abnormal in shape and size
- Abnormal chromatin structure
- Abnormal mitotic figures
describe how tumour growths are ‘graded on a microscopic histological level
describe what each grade means (1-4)
grade is the microscopic histological (histogenic classification) level - grade
- Resemblance to tissue of origin - differentiation (how similar/different do they look to the tissue of origin)
- Degree of resemblance to tissue of origin allows GRADING - Determined histologically
- Grade correlates broadly with clinical behaviour
- Precise classification important for planning treatment
what are 4 places blood can transport malignant tumours to?
blood can spread to:
- liver (haematogenous spread)
- bowel cancer
- peritoneum (transcoelomic spread)
- lymph nodes (lymphatic spread)
what does each letter stand for in TNM staging when classifying the spread of cancer?
TNM staging:
T - tumour size
N - Degree of lyph node involvement
M - extent of distant metastases (distance spread)
this is important involving the treatment of patient
