behaviours of tumours

Question 1

define invasive tumour

Answer 1

Invades adjacent normal tissue

Destroys normal tissue

Question 2

why do characteristics do tumours need in order to have the ability to invade

Answer 2

increased motility- movement
decreased adhesion
production of proteolytic enzymes.
mechanical pressure.

Question 3

what molecule enables cell to cell adhesions

Answer 3

cadherins

Question 4

what molecule enables cell to matrix adhesion

Answer 4

intergrin

Question 5

are epithelial cells polarised, and closely connected

Answer 5

yes

Question 6

are mesencymal cells loosely connected

Answer 6

yes

Question 7

what change occurs in epithelial cell of a tumour which enables them to invade and migrate

Answer 7

epithelial cells become mesenchymal cells.

Question 8

what is the function of the proteolytic enzyme matrix metalloproteinases

Answer 8

degrade extracellular matrix.

Question 9

does cancer favour matrix metalloproteinases than tissue inhibitors of metalloproteinases, and what is the function of matrix metalloproteinases

Answer 9

Yes

extracellular matrix break down

Question 10

what is the function of interstitial collagenases

Answer 10

destroy collagen types I, II, III

Question 11

what is the function of gelatinises.

Answer 11

destroy collagen type IV, gelatin

Question 12

what is the function of stomolysins

Answer 12

destroy collagen type IV, proteoglycans.

Question 13

what effect does mechanical pressure of a tumour have

Answer 13

Uncontrolled proliferation forms mass
Pressure occludes vessels
Pressure atrophy
Spread along lines of least resistance

Question 14

what is direct seeding method of metastases also known as

Answer 14

Transcoelomic- across peritoneal, plueral, pericardial cavities or CSF.

Question 15

what are the 4 methods of metastases

Answer 15

• Lymphtics- Distant or local lymph nodes
• Blood- liver, lungs, bone brain etc
• Transcoelomic- across peritoneal, plueral, pericardial cavities or CSF.
• Implantation- spillage of tumour in biopsy or surgery.

Question 16

what is the mechanical hypothesis of metastases

Answer 16

metastases is determined by anatomy- e.g lymphatic drainage of liver meets GI tract so tumour will spread along this route.

Question 17

what is the seed and soil hypothesis

Answer 17

When a plant goes to seed, its seeds are carried in all directions; but they can only live and grow if they fall on congenial soil.

Question 18

by which route do carcinomas metastases

Answer 18

lymphatic

Question 19

by which route do sarcomas metastases

Answer 19

blood spread first.

Question 20

what are the 2 types of bone metastases

Answer 20

lytic (lung) or sclerotic (prostate)

Question 21

explain the process of angiogenesis

Answer 21

new vessel formation (derived from existing vessels)

role of bone marrow as this is where the endothelial stem cells are derived from.

Question 22

when do tumours require the process of angiogeneisis to occur

Answer 22

essential if metastasis are to grow larger than 1-2 mm.

Question 23

why do we stage and grade tumours

Answer 23

Determine Prognosis – survival time, quality of life
Decide how to treat the tumour
Research – compare therapies or prognostic factors
Stage and grade are still the best markers we have for these uses

Question 24

define stage

Answer 24

How advanced is the tumour- prognosis

Question 25

define grade

Answer 25

how aggressive is the tumour? How different does it look from tissue of origin.

Question 26

tumour cells, stromal cells and inflammatory cells all promote which factor required in angiogenesis

Answer 26

VEGF

Question 27

what does TNM staging stand for

Answer 27

* T = TUMOUR * M = METASTASES * N = NODES

Question 28

does each organ have a individual TNF system

Answer 28

yes

Question 29

explain what each of these stand for

Answer 29

``` T = Size +/- extent of primary tumour M = Presence and extent of distant metastases N = Presence and number of lymph node metastases ```

Question 30

what staging is used for colorectal cancer

Answer 30

duke's staging

Question 31

explain the duke staging.

Answer 31

* 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 32

does survival rate decrease with metastases

Answer 32

Yes

Question 33

what is used to determine grading

Answer 33

histopathologies