Neoplasia Flashcards
What is a tumour?
A clinically detectable lump or swelling
Define neoplasm
An abnormal growth of cells that persist after the initial stimulus is removed
Define malignant neoplasm.
An abnormal growth of cells that persists after the initial stimulus is removed AND invades surrounding tissue with the potential to spread to distant sites.
What is a cancer?
A malignant neoplasm
What is a metastasis?
A malignant neoplasm that has spread from its original site to a new non-contiguous site.
What is dysplasia?
A pre-neoplastic alteration in which cells show disordered tissue organisation.
How do benign and malignant neoplasms differ?
Benign neoplasms remain confined to their site of origin and do not produce metastases. Malignant neoplasms have the potential to metastasise.
Describe the appearance of a malignant neoplasm to the naked eye.
Irregular outer margin and shape. May show areas of necrosis and ulceration.
What surrounds a benign tumour?
A pseudocapsule
What is meant by differentiation?
How closely the cells resemble that of the parent tissue. Well differentiated cells are less harmful than poorly differentiated cells.
What does an anaplastic mean?
Cells with no resemblance to any tissue. (Poorly differentiated)
What are the features of pleomorphism?
Increase on nuclear size
Increase in nuclear to cytoplasmic ratio
More mitotic figures
Increase variation in size and shape of cells and nuclei
Describe the relationship between pleomorphism and differentiation.
A pleomorphic cell is poorly differentiated. And so will have a high grade. Indirectly proportional.
How are grade and differentiation related?
Grade is used to indicate differentiation. A neoplasm with a high grade will be poorly differentiated.
What causes mutations in somatic cells?
Initiators and promotors
What is a somatic cell?
A cell that forms the body. Any cell other than a germ cell
What is an initiator?
A mutagenic agent
What does a promoter do?
Causes cell proliferation.
What is a monoclonal population?
A collection of cells that all originate from a single founding cell.
What is progression?
The process by which a neoplasm is formed from a monoclonal population. It is characterised by the accumulation of more mutations
What is lysonisation?
When, during early embryogenesis, one allele is randomly inactivated in each cell.
How do you name benign neoplasms?
End in -oma
How do you name a malignant neoplasm of the epithelia?
End in -carcinoma.
How do you name a stromal malignant neoplasm?
Ends in -sarcoma.
