Characteristics of Tumour Flashcards
define cancer
the uncontrolled cell growth which can invade and spread to distant sites o the body
define tumour
an abnormal swelling - synonymous with neoplasm - abnormal and excessive growth of tissue
persists with abnormal growth in the absence of an initiating stimulus
what are the most common incidences of cancers in men and women
men - prostate, lung, colon and rectum
women - breast, lung, colon and rectum
which are the most common deaths from cancer in men and women
men - lung, prostate, colon rectum
women - lung, breast, colon, rectum
what are the 4 categories in which we can characterise a tumour
rate of growth
differentiation
local invasion
metastasis
what are the two subtypes of cancer
malignant and benign
what is the rate of growth of cancers determined by
doubling time of the cells (mitotic activity) - rate at which the cells die
what is special about malignant cells
grow more rapidly - rate of growth linked to prognosis
what do we mean by the differentiation of malignant cells in tumour
the extent that neoplastic cells histologically resemble its cell or tissue or origin
what is pleomorphism
cells and nuclei varying in size and shape - indicates malignancy
what are the 3 grades of differentiation in a tumour
well differentiated - cells closely resemble those of normal tissue - grade 1 (low)
moderately differentiated - grade 2
poorly differentiated - cells hardly resemble those of normal tissue - grade 3 - (high)
what is the differentiation between a malignant and a benign tumour
malignant - anywhere between well to poorly differentiated
benign - well differentiated
what is anaplasia
neoplasms comprise of such poorly differentiated cells that they show no resemblance to that of normal tissue - hallmark of malignancy
what are some examples to look for in abnormal nuclear morphology
nuclei - appear too large for the cell
variable nuclear outlines
hyperchromatism - too dark
what are 2 hallmarks of malignancies
mitoses - malignant cells have atypical bizarre mitotic figures
loss of polarity
local invasion
what are the characteristics of a benign tumour
cohesive, slow growing, localised to site of origin, no capacity to invade or metastasise
why are malignant tumour so dangerous
infiltrate, invade and destroy surrounding tissue - local invasion
penetrates vessel walls and lymphatics
what is the definition of metastasis
spread of a tumour to sites physically discontinuous with the primary tumour
what are the 4 pathways of spread of metastasis
direct seeding
lymphatic spread
haematogenous spread
implantation
what is direct seeding in tumours
malignant neoplasm penetrates into natural body cavity - most common in the peritoneal cavity
describe lymphatic spread in cancers
most common pathway for carcinomas - pattern of lymph node involvement follows the routes of lymphatic drainage
describe haematogenous spread in cancers
invasion into blood vessels - typical for sarcomas but also seen in carcinomas - cells follow th venous flow draining site of the neoplasm
what is implantation in tumour cells
accidental spillage of tumour cells during surgery
what is stroma in cancer
connective tissue framework that supports cells
what is the role of a stroma in cancer
provides mechanical support, intracellular signalling and nutrition
around tumours shows a desmoplastic reaction - growth of tissue containing cancer associated fibroblasts, blood vessels and myofirbroblasts
what do the clinical complications of cancer depend on
location, cell of origin and behaviour
what effects on the body can a tumour have
local - compression and displacement - pituitary placement = loss of vision , destruction from a malignant tumour
metabolic - non-specific (cachexia malignant only)
tumour - specific such as endocrine effects on a thyroid tumour
due ot metastases
