Neoplasia 2 Flashcards
What is the difference between a benign and malignant tumour?
Malignant tumours have the ability to invade and metastasise.
What is the systemic consequence of metastasis?
There is a greatly increased tumour burden, and vast numbers of malignant cells.
What are the three steps involved in metastasis?
Cells must grow and invade at a primary site, they then must enter a transport system and become lodged somewhere followed by growth at this new, secondary site.
What must metastasising cells evade in order to be successful?
The immune response from the body.
What three properties of an cancerous epithelial cell change when it invades?
Motility, stromal proteolysis and altered adhesion
What is EMT?
Epithelial to mesenchymal transition. This occurs because cells undergo change when they invade tissue.
What is responsible for altered adhesion between 2 malignant cells?
E-Cadherin
What is responsible for altered adhesion between malignant cells and other stromal proteins?
Altered integrin expression.
What is a Matrix metalloproteinase?
These degrade the basement membrane and stroma and allow invasion of cells.
What is a cancer niche?
This is the name for the cells surrounding the tumour which are taken advantage of, and secrete some growth factors as well as proteases.
What is the major change in a cell which leads to altered motility?
Changes in the actin cytoskeleton.
Through what structures can cancerous cells travel to distant sites?
Blood vessels, lymphatic system and coelomic spaces.
What is extravasation?
When cells travel to a distant site in a vessel, this is the process in which they leave the vessel.
What is the name for growth of tumour cells once they reach a distant site?
Colonisation.
What is tumour dormancy?
This is where tumour free individuals harbour micrometastisis
What is the most common cause of malignant tumour relapses?
Growth of micrometastasis.
What determines the second neoplasm site?
This depends on where the fluid drains to. For lymph it is lymph nodes, for blood vessels next capillary bed (lung or liver) and for coelomic fluid it is generally adjacent organs.
What can be said about the niche at a second cancer site?
This must be a similar environment which means that requirements for tumour growth are met.
Name some neoplasms which commonly metastasis to bone.
Prostate, thyroid, breast, bronchus, kidney.
What is seen on an X-ray of bone which is affected by secondary neoplasm?
Areas of osteolysis are present. When the primary is prostate, then instead areas of dense bone are seen.
Name a carcinoma which rarely metastasises
Basal cell carcinoma
In what cases is a tumour still malignant if it does not metastasis?
If it has invaded local tissue.
What are paraneoplastic syndromes?
These are systemic effects of the neoplasm, for example tumour burden, hormones and other effects.
Name some local complications of neoplasms.
Ulceration leading to bleeding, blocking of tubes, damage to local tissue and compression of adjacent structures.
What are common systemic effects of cancer?
This is caused by the parasitic effect of increased tumour burden. It includes weightloss, cachexia, reduced appetite, immunosuppression and thrombosis.
Why do benign tumours of endocrine glands usually secrete hormones?
They are usually well differentiated.
Name a malignant neoplasm which secretes ADH and ACTH.
Bronchial small cell carcinoma.
What hormone does bronchial squamous cell carcinoma secrete?
PTH-like hormone.
There are some miscellaneous systemic effects associated with cancer. Name a few:
Neuropathy of brain and peripheral nerves, myositis, fever, skin abnormalities (in pigmentation and itching)
