Neoplasia 1 Flashcards
(32 cards)
What is a malignant neoplasm?
- An abnormal growth of cells that persists after the initial stimulus has been removed and invades surrounding tissue with potential to spread to distant sites
What is a neoplasm?
- An abnormal growth of cells that persists after the initial stimulus is removed
What is dysplasia?
- Pre-neoplastic growth which is reversible
- Can lead to neoplasm which is irreversible
What are the two different types of malignant neoplasms (cancerous)?
- Primary: original site
- Secondary: metastasis
What is the difference in behaviour of benign and malignant neoplasms?
- Benign: remain confined to site of origin and don’t metastases
- Malignant: have potential to metastases
What does a benign neoplasm look like to the naked eye?
- Has pushing outer margin as grows confined in a local area
What does a malignant neoplasm look like to the naked eye?
- Irregular outer margin and shape
- May show areas of necrosis and ulceration
Histologically what do malignant and benign neoplasms look like?
- Benign: well differentiated (closely resembles the parent tissue)
- Malignant: ranges from well to poorly differentiated
What is the term given to cells with no resemblance to any tissue?
- Anaplastic
What differences are seen in the individual cells with worsening differentiation?
- Cells have increasing nuclear size -> nuclear hyperchromasia
- More mitotic figures
- Increased variation in size and shape of cell and nucleus
What is hyperchromasia?
- Increased nuclear to cytoplasm ratio
What is pleomorphism?
- Increased variation in size and shape of cell and nucleus
Potential cancers are given a grade what does a higher grade mean?
- More poorly differentiated -> poorer outcome
Put these in order of most severe and say why:
- Dysplasia
- Carcinoma in situ
- Invasive carcinoma
- Invasive carcinoma: irreversible and has penetrated the basal membrane
- Carcinoma in situ: irreversible but hasn’t penetrated basal membrane
- Dysplasia: reversible
Are most cancers due to genetic disposition or environmental factors?
- Environmental factors
What two things are needed for the expansion of a mutant population of cells?
- Initiators: mutagenic agents
- Promoters: cell proliferation
Give some examples for initiators.
- Chemicals
- Infections
- Radiation
Why does germ line mutations increase the risk of neoplasm?
- Mutations already present so only one more is needed
- Normally need two
How do we know that cancer is monoclonal?
- Enzyme G6PD
- Early in embryogenesis one allele is randomly inactivated this is called lyonisation.
- In neoplasia the mutated cells are all either maternal/paternal hence they’re monoclonal
Which are the two types of cell that need to be genetically affected for the two hit theory to be activated?
- Proto-oncogenes -> oncogenes
- Tumour suppressor genes -> inactivated
What is taken into account when naming a neoplasm?
- Site of origin
- Benign/malignant
- Type of tissue the tumour forms
- +/- gross morphology
If a neoplasm is benign what is it’s suffix?
- -oma
If a neoplasm is malignant what does it end in and if it’s epithelial what does it end in?
- -carcinoma
- -stroma
What are epithelial neoplasms also known as and what are the other types?
- Polyps
- Stratified squamous - squamous papilloma (finger-like projections)
- Transitional cell papilloma e.g. Bladder mucosa
- Glandular - adenoma e.g. Adenomatous
