MOD Session 8- Neoplasia 1 Flashcards
(30 cards)
Define malignant neoplasm
An abnormal growth of cells that persists after removal of the stimulus and invades surrounding tissue with the potential to spread to distant sites.
Define neoplasm
An abnormal growth of cells that persists after the initial stimulus is removed.
What is a neoplasm a type of?
Tumour
Define tumour
A clinically detectable lump or swelling.
What is a cancer?
A malignant neoplasm
Define metastasis
A malignant neoplasm that has spread from its original (primary) site to a new non-contiguous (secondary) site.
What is dysplasia?
A pre-neoplastic alteration
Cells show disordered tissue organisation.
Why is dysplasia not neoplastic?
Because the change is reversible.
What is the behavioural difference between benign and malignant tumours?
Benign tumours remain at their site of origin and don’t metastasise, whereas malignant tumours have the potential to metastasise.
Why does the surface break in malignant tumour and cause ulceration?
Because the tumour is growing faster than a new blood supply can be produced.
What are the macroscopic differences between benign and malignant tumours?
Benign- grow in a confined local area and have a pushing outer margin.
Malignant- have an irregular outer margin and shape. They may show necrosis and ulceration.
What does differentiation refer to?
How well the cells resemble a normal, parent tissue.
What are anaplastic cells?
Cells that have no resemblance to any tissue.
What is pleomophism and what happens to the cells?
It is worsening differentiation that causes cells to:
- have increasing nuclear size
- have increased nuclear to cytoplasmic ratio
- have increased nuclear staining (nuclear hyperchromasia)
- have more mitotic figures
- have increasing variation in cell shape and size
What is nuclear hyperchromasia?
Increased nuclear staining
How is differentiation indicated?
Grading.
High grade= poor differentiation.
What is neoplasia caused by?
Accumulations of mutations in somatic cells.
What are the steps of neoplasm mutation?
- initiators cause mutations to occur.
- promoters cause cell proliferation.
- these two together produce an expanded monoclonal population.
- a process called progression in which further mutations occur cause a neoplasm to emerge from the monoclonal population.
What does a proto-oncogene become when it is abnormally activated?
Oncogene.
What happens to a tumour-suppressor gene when there is a genetic alteration?
Becomes inactivated.
What is the suffix for benign neoplasms?
Oma
What is the suffix for malignant epithelial neoplasms?
Carcinoma
What is the suffix for malignant stromal neoplasms?
Sarcoma
What is leukaemia?
A malignant neoplasm of blood-forming cells arising in the bone marrow
