CP 22 - Behaviour of Tumour

Question 1

does patients with basal cell carcinoma usually have metastasis

Answer 1

basal cell carcinoma does not usually metastasis

Question 2

how can tumour cells achieve greater motility or less adhesion

Answer 2

• mutation of E-cadherin leads to loss of cell-cell adhesion and contact inhibition
• changes in integrin expression leads to decreased cell-matrix adhesion

Question 3

what does cadherins do

Answer 3

cell to cell adhesion molecules

Question 4

what does integrins do

Answer 4

cell to matrix adhesion molecules

Question 5

what are the difference between epithelial cell and mesenchymal cells

Answer 5

E - tightly connected, polarised and tethered

M - loosely connected, able to migrate

Question 6

what must the tumour cells undergo before metastasis?

Answer 6

epithelial - mesenchymal transition (in cancer, epithelial cells gain mesenchymal properties and so can invade and migrate)

Question 7

what will happen after the epithelial-mesenchymal transition

Answer 7

proteolytic enzymes are released in order to digest through the walls and start the process of metastasis

Question 8

which enzyme is responsible for degrading extracellular matrix

Answer 8

matrix metalloproteinases

Question 9

what are the specific proteolytic enzymes for each collagen

Answer 9

interstitial collagenases - collagen I, II, III

gelatinases - collagen IV, gelatin

stomolysins - collagen IV, proteoglycans

Question 10

how can mechanical pressure cause metastasis

Answer 10

uncontrolled proliferation - mass

pressure occludes vessels

pressure atrophy
spreading lines of least resistance

Question 11

what are the different routes for metastasis

Answer 11

lymphatic, blood (haemogenisus), transcoelomic, implantation

Question 12

what are the different stages of metastasis

Answer 12

detachment invasion (from original sites towards blood vessels) - intravasation - survival against host defences - adherence extravasation (adhered to the vessels wall) - angiogenesis - growth

Question 13

what route does carcinoma usually use to spread?

Answer 13

lymphatic spread first

Question 14

what route does sacromas usually use to spread?

Answer 14

blood spread first

Question 15

which cancers usually have bone metastasis

Answer 15

thyroid, breast, lungs, kidney, prostate

Question 16

which cancers usually have metastasis through transcoelomic route?

Answer 16

ovarian

Question 17

which cancer spread to brain and adrenal gland

Answer 17

lung cancer

Question 18

what is a rough guide for stage?

Answer 18

how advance is the tumour, has the cancer spread and if so what is the extend of spread

Question 19

what is a rough guide for grade

Answer 19

how aggressive is the tumour - how different does it look from tissue of origin

Question 20

what does T, M and N means in the TMN system

Answer 20

T - tumour
M - metastasis
N - Node

Question 21

for breast cancer, how is the T staging work?

Answer 21

Tis - in situ disease
T1 - 5cm
T4 - involving skin or chest wall

Question 22

for breast cancer, how is the N staging work?

Answer 22

N0 - no nodes
N1 - ipsilateral nodes
N2 - >node involvement

Question 23

how is the staging of a particular cancer calculated?

Answer 23

combination of clinical, radiological, pathological diagnoses

Question 24

what is the staging of breast cancer

Answer 24

0 - Tis 
1 - T1, N0, M0,
2 - T1-2, N1 or T3 
3 - T(any), N2 or T4
4 - T(any), N(any), M1

Question 25

what is another Dukes Staging for colorectal cancer

Answer 25

A = invades into, but not through bowel wall 
B = invades through the bowel wall but with no lymph node metastases 
C = local lymph nodes involved
D = distant metastases

Question 26

what does grading take into account?

Answer 26

differentiation (resemblance to tissue of origin), nuclear pleomorphism and size, mitotic activity, necrosis