Introduction to clinical medicine: CARCINOGENESIS AND NEOPLASIA Flashcards
What is basal cell carcinoma
cancer of the skin, only invades local areas and does not spread to other parts of the body
how do you cure basal cell carcinomas
complete local excision
why does basal cell carcinoma not spread
the cells do not circulate round the body
what is leukaemia
cancer of lymphocytes
what is the difference between basal cell carcinoma and leukaemia
white blood cells can circulate around the body and spread
unlike other cancers that cause tumours, leukaemia is the over production of abnormal white blood cells that circulate instead of mass to form a tumour
why can leukaemia be referred to of cancer of the bone marrow and blood
because WBC are made in the bone marrow and circulate in the blood
which lymph node are breast cancer cells found to spread to
axillary lymph nodes under the arm
what is a carcinoma`
a type of cancer that arises from the epithelial cell of the skin of the lining of the eternal organ (affects surfaces)
define metastases
development of secondary malignant growth (separate from the primary site of cancer)
give an example of where micro metastases may occur
detection of cancerous cells in axillary node under the arm from breast cancer
how is micro metastases dealt with
Adjuvant therapy - extra treatment given after surgical excision
name 2 types of chemotherapy
Conventional and targeted
define carcinogenesis
transformation of normal cells to neoplastic cells through permanent genetic alternation/mutation
name the classes of carcinogen (what may initiate cancer)
chemical viral ionising and non-ionising hormone, parasites, mycotoxins miscellaneous
define neoplasm
A lesion resulting from the AUTONOMOUS (or relatively autonomous) ABNORMAL growth which PERSISTS after initiating stimulus has been removed (how you know its autonomous … a neoplasm)
factors of neoplasia
new growth
autonomous
persistent
abnormal
true or false: neoplastic cells derive from nucleated cells
True. this is why RBC cells can not go through neoplasm but their precursors do.
what are the 2 mains structures of neoplasm
- neoplastic cell
- stroma
why does the risk of a neoplasm increase with age
the more divisions a cell has gone through, the more likely it will go through a neoplastic transformation
what is a malignant tumour
a tumour that invades surrounding tissues
what is a benign tumour
a tumour that does not invade surrounding tissue
what are some of the main differences between a malignant and benign tumour
benign tumours are slower in division - due to a a slower mitotic rate
benign tumours are exophytic whilst malignant tumours are endophytic
necrosis is rare in benign tumours and metastases never occurs, with the cells of a benign tumour looking like the normal surrounding tissues
what are the classifications of tumour
benign epithelial
Malignant epithelial
Benign connective tissue
Malignant connective tissue
what type of tumour is a PAPILLOMA
Benign epithelial tumour - non-glandular or non-secretory
what type of tumour is a ADENOMA
Benign epithelial tumour - glandular or secretory
what type of tumour is a CARCINOMA
Malignant epithelial tumour - non-glandular
what type of tumour is a ADENOCARCINOMA
Malignant epithelial tumour - glandular
define invasion
direct extension and penetration by cancer cells into neighbouring tissues
define metastasis
secondary tumour
what is the main treatment does to remove micro-metastasis
adjuvant therapy
what is adjuvant therapy
follow up surgery or chemotherapy done to remove secondary tumours
what 2 qualities are important in order for tumours to invade
invading cells need to be able to ‘move through’ and ‘chew through’ a basement membrane
move - cell motility
chew - enzymatic activity - e.g. proteases
what are the 5 stages of metastasis
Intravasation Evasion host immune defence Extravasation Growth at the metastatic site Angiogenesis
what is involved in intravasation
leaving the site of primary tumour. involves invasion of the cell membrane and cell motility
what are the 3 methods cells use during avoidance of host immune defence
- Aggregation with platelets - hide within platelets
- shedding of surface antigens - lymphocytes detect and attack these instead as they may be non self antigens
- adhesion to other tumour cells - lymphocytes unable to digest cells within the clump of cells. protection
how do cells know where to exit into tissues or lymph nodes (for example) during extravasion
it is believed they they detect receptors at secondary tumour site and adhesion occurs
how are these cells able to grow
cancer has growth factors that promote the growth of further neoplastic cells, acting as a positive feedback loop
name 2 things a cell produces to promote angiogenisis
vascular endothelial growth factor
basic fibroblast growth factor
name 3 treatments that inhibit angiogenesis
possible treatment
angiostatin
endostatin
vasculostatin
statins reduce levels of cholesterol in blood - which may prevent the build of particular components
why would cells die if they were more than 1mm in thickness
it would be too deep for oxygen to pass through and provide to deeper cells, causing them to die
