Neoplasia 1 Flashcards
(26 cards)
What is neoplasia?
Abnormal growth of cells that persists once the stimulus is removed
How does dysplasia differ from neoplasia?
Dysplasia is when cells show disordered tissue organisation and is a reversible process whereas the neoplasia is irreversible
How do tumours differ from neoplasms?
Neoplasia is a type of tumour
A tumour is any clinically detectable lump
What is meant by the term metastasis?
A metastasis is a malignant neoplasm that has spread from its original site to a new non-contiguous site. The original location is the primary site and the place to which it has spread is a secondary site
In what type of neoplasms would anaplastic cells be seen?
Malignant
Cells range from poorly differentiated so some cells present may have no resemblance to any other tissue type whereas cells of a benign tumour are well differentiated
How does the macroscopic appearance of benign and malignant neoplasms differ?
B - Grow in confined, local area and have a pushing outer margin
M - Have an irregular outer margin, areas of necrosis and ulceration on the surface
List the microscopic appearances of malignant neoplastic cells
Hyperchromasia, pleomorphisms, increased ratio of nuclear size to cytoplasm, increased number of mitotic figures
What is tumour grade?
The description of a tumour on a scale ( 1-4) based on how abnormal the tumour cell
What would a grade of G3 indicate and in which sort of cancers would this be the most relevant prognosis
Poorly differentiated cells present in the neoplasm
More relevant in breast cancers
How does invasive malignancy differ from in-situ malignancy?
Invasive penetrates basement membrane
How can scientists prove that neoplasms are made up of monoclonal cells?
- Use of X-linked enzyme glucose-6-phosphate dehydrogenase
- Different alleles of the gene code for different isoenzymes are resent in the population
- One allele present in the maternal egg cell will be inactivated in embryogenesis in process called lionisation
- In women who are heterozygous fro this gene, their normal tissue will be a patchwork of the heat labile and heat stable isoenzymes
- However neoplastic tissues only one isoenzyme will be expressed
Which genes are altered in neoplasia?
Proto-oncogenes are activated to form oncogenes and tumour suppressor genes are inactivated
What is a common name for benign germ cell tumours and where do they commonly form?
Teratomers
Ovaries, arise from pluripotent cells
What is a carcinoma and list some examples?
Malignant neoplasm of the epithelial tissue
Squamous cell carcinoma, transitional cell carcinoma, adenocarcinoma
What is a sarcoma and list some examples?
Malignant neoplasm of stromal tissue
Leiomyosarcoma, fibosarcoma, chondrosarcoma, malignant glioma, liposarcoma
List some benign mesenchymal tumours?
Leiomyoma, fibroma, chondroma, lipoma, glioma, neuroma
What are neuroendocrine tumours and list some examples?
Tumours that arise from cells distributed throughout the body Phaeochromocytoma, small cell carcinoma of bronchus, carcinoid tumours
What are blastomas and when do they commonly occur?
Formed from immature precursor cells
Occur mainly in children
What is leukaemia?
Malignant neoplasm of blood-forming cells arising in the bone marrow
What is lymphoma?
Malignant neoplasms of lymphocytes mainly affecting lymph nodes
Outline the differences between a papilloma and polyp
Papilloma - any tumour with finger like projections
Polyp - small benign growth protruding from a mucous membrane
What tissues does an adenoma involve?
Benign tumour of glands in epithelial tissue
Define malignant neoplasms
an abnormal growth of cells that persists after the initial stimulus is removed AND invades surrounding tissue with potential to spread to distant sites
What is a tumour?
Any clinically detectable lump or swelling. A neoplasm is just one type of tumour
