Session 8 Flashcards
Define neoplasia
An abnormal growth of cells that persists 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 potential to spread to distant sites
Define tumour
Any clinically detectable lump or swelling
Define cancer
Any malignant neoplasm
Define metastasis
A malignant neoplasm that has spread from its original site (primary site) to a new non-contiguous site (secondary site)
Define dysplasia
A pre-neoplasticism alteration in which cells show disordered tissue organisation (reversible)
Compare dysplasia and neoplasia
Neoplasia = irreversible
Dysplasia = reversible
Do benign neoplasms produce metastases?
No - remain confined to their site of origin
Describe the appearance of a benign neoplasm to the naked eye with regards to its outer margin in particular
Has a regular ‘pushing’ outer margin and grows in a confined area
Benign neoplasms may push on local structures causing…
Inflammation
Describe the appearance of cells of a benign neoplasm under the microscope
Cells closely resemble the parent tissue - well differentiated
Do malignant neoplasms have the potential to metastasise?
Yes, by definition
Describe the appearance of a malignant neoplasm to the naked eye
Irregular outer margin and shape
May show necrosis/ulceration
Describe the appearance of the cells of a malignant neoplasm under a microscope
Cells range from well to poorly differentiated
What is meant by the term anaplastic?
Cells have no resemblance to any tissue
Compare the cells seen in malignant neoplasms with the cells seen in benign neoplasms
Benign - well differentiated cells (resemble parent tissue)
Malignant - poorly to well differentiated (a range)
Describe the varying degrees of differentiation seen in benign and malignant neoplasms under the microscope
Benign - cells well differentiated, closely resemble parent tissue
Malignant - cells range from well to poorly differentiated
Name 5 changes seen in cells due to worsening differentiation as seen in malignant neoplasms
Nuclear hyperchromasia
Increased nuclear:cytoplasm ratio
Increased mitoses (mitotic figures)
Larger nucleus
Cellular and nuclear size variation (pleomorphism)
What is nuclear hyperchromasia?
Increased nucleus staining due to increased DNA content
Clinicians use the term __________ to indicate differentiation
Grade
Clinicians use the term grade to indicate differentiation.
High grade = _________ differentiated
Poorly
Neoplasm is caused by an accumulation of _____________ in somatic cells
Mutations
What sort of factors are the most important causes of mutations?
Extrinsic/Environmental Factors
Mutations are caused by initiators and promoters.
What is the function of an initiator?
What is the function of a promoter?
Mutagenic agent - introduces mutation
Causes cell proliferation