13 Neoplasia 1 Flashcards
Define ‘Neoplasm’.
Abnomal growth of cells- persists after initial stimulus removed
Define ‘Malignant Neoplasm’.
(Abnomal growth of cells- persists after initial stimulus removed) + invades surrounding tissue w./ potential spread to distant sites
Define ‘Tumour’.
Clinically detectable lump/ swelling.
Define ‘cancer’
Malignant neoplasm
Define ‘metastasis’
Malignant neoplasm- spreads from original site to new non-contiguous site (secondary site)
What is ‘dysplasia’?
Pre-neoplastic alteration- cells= disordered
How is dysplasia different from neoplasia?
Dysplasia=reversible, neoplasia isn’t
What’s the difference between benign and malignant neoplasms?
Benign- remain confined to site of origin don’t produce matastases Malignant- have potential to metastasise
How do benign and malignant neoplasms appear different to the naked eye?
Benign- grow- confined area- pushing outer margin (pseudo capsule) Malignant- irregular outer margin, shape + potential areas of necrosis/ ulceration
How do benign and malignant neoplasms appear different under the microscope?
Benign= well differentiated (resemble parent tissue) Malignant= range- poorly–> well differentiated
What are anaplastic cells?
Cells- no resemblance to any tissue
How do cells with WORSENING differentiation appear under the microscope?
-Increased nuclear size to cytoplasmic ratio -Increased nuclear staining (hyperchromasia) -More mitotic figures -Increased variation- size and shape of cells and nuclei (pleomorphism)
If a neoplasm is labelled as ‘high grade’ by a clinician, what does this mean?
It is poorly differentiated
What causes neoplasia?
Mutations caused by: -initiators (mutagenic agents) - e.g. chemicals/infections -promoters (cell proliferation) (mutations can be inherited/external) –>cause expanded, monoclonal (originating from same cell) population of mutant cells then: PROGRESSION- accumulation of more mutations
What is ‘lyonisation’?
Random inactivation of 1 allele in early female embryogenesis
What are proto-oncogenes?
Genes coding for proteins responsible for cell proliferation
What are tumour suppressor genes?
Protect cell from becoming cancerous- slow cell division, correct mistakes etc.
What is an oncogene?
When proto-oncogene= abnormally activated (favour neoplasm formation)
What do the names of all BENIGN neoplasms end in?
-oma
What do the names of MALIGNANT EPITHELIAL neoplasms end in?
-carcinoma
What do the names of MALIGNANT STROMAL neoplasms end in?
(stromal= CT cells) -sarcoma
What is a carcinoma called if it has not invaded through the basement membrane?
in-situ
What is a carcinoma called if it has penetrated through the basement membrane?
invasive
What is the name of.a malignant neoplasm of blood forming cells arising in bone marrow?
Leukaemia
