Characteristics of Tumour

Question 1

define cancer

Answer 1

the uncontrolled cell growth which can invade and spread to distant sites o the body

Question 2

define tumour

Answer 2

an abnormal swelling - synonymous with neoplasm - abnormal and excessive growth of tissue
persists with abnormal growth in the absence of an initiating stimulus

Question 3

what are the most common incidences of cancers in men and women

Answer 3

men - prostate, lung, colon and rectum

women - breast, lung, colon and rectum

Question 4

which are the most common deaths from cancer in men and women

Answer 4

men - lung, prostate, colon rectum

women - lung, breast, colon, rectum

Question 5

what are the 4 categories in which we can characterise a tumour

Answer 5

rate of growth
differentiation
local invasion
metastasis

Question 6

what are the two subtypes of cancer

Answer 6

malignant and benign

Question 7

what is the rate of growth of cancers determined by

Answer 7

doubling time of the cells (mitotic activity) - rate at which the cells die

Question 8

what is special about malignant cells

Answer 8

grow more rapidly - rate of growth linked to prognosis

Question 9

what do we mean by the differentiation of malignant cells in tumour

Answer 9

the extent that neoplastic cells histologically resemble its cell or tissue or origin

Question 10

what is pleomorphism

Answer 10

cells and nuclei varying in size and shape - indicates malignancy

Question 11

what are the 3 grades of differentiation in a tumour

Answer 11

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)

Question 12

what is the differentiation between a malignant and a benign tumour

Answer 12

malignant - anywhere between well to poorly differentiated

benign - well differentiated

Question 13

what is anaplasia

Answer 13

neoplasms comprise of such poorly differentiated cells that they show no resemblance to that of normal tissue - hallmark of malignancy

Question 14

what are some examples to look for in abnormal nuclear morphology

Answer 14

nuclei - appear too large for the cell
variable nuclear outlines
hyperchromatism - too dark

Question 15

what are 2 hallmarks of malignancies

Answer 15

mitoses - malignant cells have atypical bizarre mitotic figures

loss of polarity

local invasion

Question 16

what are the characteristics of a benign tumour

Answer 16

cohesive, slow growing, localised to site of origin, no capacity to invade or metastasise

Question 17

why are malignant tumour so dangerous

Answer 17

infiltrate, invade and destroy surrounding tissue - local invasion
penetrates vessel walls and lymphatics

Question 18

what is the definition of metastasis

Answer 18

spread of a tumour to sites physically discontinuous with the primary tumour

Question 19

what are the 4 pathways of spread of metastasis

Answer 19

direct seeding
lymphatic spread
haematogenous spread
implantation

Question 20

what is direct seeding in tumours

Answer 20

malignant neoplasm penetrates into natural body cavity - most common in the peritoneal cavity

Question 21

describe lymphatic spread in cancers

Answer 21

most common pathway for carcinomas - pattern of lymph node involvement follows the routes of lymphatic drainage

Question 22

describe haematogenous spread in cancers

Answer 22

invasion into blood vessels - typical for sarcomas but also seen in carcinomas - cells follow th venous flow draining site of the neoplasm

Question 23

what is implantation in tumour cells

Answer 23

accidental spillage of tumour cells during surgery

Question 24

what is stroma in cancer

Answer 24

connective tissue framework that supports cells

Question 25

what is the role of a stroma in cancer

Answer 25

provides mechanical support, intracellular signalling and nutrition
around tumours shows a desmoplastic reaction - growth of tissue containing cancer associated fibroblasts, blood vessels and myofirbroblasts

Question 26

what do the clinical complications of cancer depend on

Answer 26

location, cell of origin and behaviour

Question 27

what effects on the body can a tumour have

Answer 27

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