TREATMENT OF CANCER

Question 1

How does chemotherapy work?

Answer 1

it kills cells that are rapidly dividing and cancer cells divide the fastest

Question 2

chemotherapy isnt targeted but outline how some specificty occurs?

Answer 2

cancer cells are unable to repair DNA damage whilst normal cells can

Question 3

why do we use combination chemotherapy?

Answer 3

chemotherapy drugs affect cancer cells at different points in the cell cycle, using a combination of drugs increases the chance that all of the cancer cells will be eliminated.

Question 4

what are some aims of chemotherapy?

Answer 4

curative
adjuvant given after a radiotherapy/surgery
neo-adjuvant - given before rasdiotherapy/surgery
palliatively

Question 5

what are the classes of chemotherapy agents?

Answer 5

alkylating agents, plant alkaloids, antimetabolites, anthracyclines, topoisomerase inhibitors and corticosteroids.

Question 6

what percentage of cancer patients have radiotherapy during the course of their disease?

Answer 6

50%

Question 7

what strength radiation is radiotherapy?

Answer 7

Mega voltage radiation

Question 8

what is compton scattering?

Answer 8

the scattering of a photon after an interaction with a charger particle, usually an electron

Question 9

outline the mechanism of radiotherapy?

Answer 9

ionising radiation ionises water and oxygen which creates free radicals which cause DNA damage.

Question 10

what are the 2 types of radiotherapy?

Answer 10

external beam radiotherapy

brachytherapy

Question 11

why is radiotherapy given as fractions?

Answer 11

so that the healthy tissue that is damaged can recover in between doses

Question 12

what is the proces of conventional external beam irradiation?

Answer 12

2-D beams use kilo voltage therapy x-ray units to generate high energy X-rays

Question 13

what is stereotactic radiotherapy used for?

Answer 13

used for small, isolated tumors outside the brain and spinal cord, often in the liver or lung. It may be an option when you cannot have surgery due to age, health problems, or the location of the tumor.

Question 14

what is 3D conformal radiation therapy?

Answer 14

a cancer treatment that shapes the radiation beams to match the shape of the tumor.

Question 15

what is brachytherapy?

Answer 15

internal radiation therapy which is achieved by putting a sealed or unsealed source of radiation inside or next to the area requiring treatment

Question 16

pros and cons or brachytherapy?

Answer 16

tumour can be treated with very high doses in a small time frame
but tumour must be accessible and well-demarcated

Question 17

what is a Gray?

Answer 17

1 joule of energy absorbed per KG of matter

Question 18

what is fractionated radiotherapy?

Answer 18

when radiotherapy is given over several days and each dose is called a fraction. Typical doses for a fraction are 2Gy (gray)

Question 19

what are the differences between chemotherapy and radiotherapy?

Answer 19

chemo targets proliferating cells whilst radio targets the tumour
chemo uses drugs and radio uses high energy waves
chemo targets multiple parts of the body whilst radio targets a single area

Question 20

what are the side effects of chemo?

Answer 20

alopecia
stomatitis and mucotitis
nausea and vomiting
immunosuppression
anaemia
bleeding/bruising (pancytopenia)

Question 21

what is chronic toxicity?

Answer 21

the development of adverse effects as the result of long term exposure to a toxicant or other stressor

Question 22

what are the acute side effects of radiotherapy?

Answer 22

erythematous, itchy, dry skin
oesophagitis
dysphagia
cough and shortness of breath
nausea
vomiting
anaemia
leucopenia
leathery
myelitis

Question 23

what are the chronic side effects of radiotherapy?

Answer 23

infertility
hair loss
fibrosis
telangiectasia
late ulceration
fistula
structure
necrosis
growth retardation 
myelofiborisis
permanent nerve damage

Question 24

what is a risk of having chemo/radiotherapy at younger ages?

Answer 24

the chance of secondary cancers

Question 25

what are some modes of resistance to anticancer drugs?

Answer 25

change in binding affinity to target enzymes
formation of drug-inactivating enzymes
production of reactive chemicals
increased nucleic acid repair mechanisms
reduced activation of pro-drugs

Question 26

what is MDR1?

Answer 26

multidrug resistance mutation 1

Question 26

what is MDR1?

Answer 26

multidrug resistance mutation 1

Question 27

what is MDR1?

Answer 27

multidrug resistance mutation 1

Question 28

how does MDR1 work?

Answer 28

The MDR1 gene codes for the production of a protein known as p-glycoprotein. This sits on the cell membrane of these cancer cells and pumps chemotherapy drugs out of the cell. = resists chemotherapy drugs

Question 29

what is primary reisstance?

Answer 29

when a malignant tumour doesnt respond to immunotherapy

Question 30

what is adaptive resistance?

Answer 30

when a cancer is recognized by the immune system but it protects itself by adapting to the immune attack.

Question 31

what are some limitations of cytotoxic chemotherapy?

Answer 31

• lacks specifity
• toxic and side effects
• lack of effectiveness
• lack of individualism

Question 32

whats the function of epidermal growth factor receptor (EGFR)?

Answer 32

signalling molecules bind to it and cause downstream signalling which results in signal transduction cascade leading to DNA synthesis and cell proliferation

Question 33

what can overexpression of EGFR cause?

Answer 33

uncontrolled cell division = cancers

Question 34

how has the recognition of the EGFR receptor been used in pharmacology?

Answer 34

EGFR inhibitors
monoclonal antibodies that block the extracellular ligand binding domain
inhibitors of EGFR tyrosine kinase

Question 35

what is PD-1 and PD-L1?

Answer 35

programmed cell death protein 1 and its ligand

Question 36

what happens when PD-1 and PD-L1 bind?

Answer 36

it helps keep T cells from killing other cells, including cancer cells.
so we use these as drug targets

Question 37

what is an example of a PD-1 inhibitor?

Answer 37

permbrolizumab

Question 38

whats an example of a PD-L1 inhibitor?

Answer 38

atexolizumab

Question 39

what is CTLA-4?

Answer 39

cytotoxic T-lymphocyte associated protein 4 (inhibits immune cell activity)

Question 40

what is the angiogenic switch?

Answer 40

when a tumour starts to stimulate the growth of new blood vessels

Question 41

whats the principle stimulus for the angiogenic switch?

Answer 41

oxygen deprivation

Question 42

what are some examples of pro-angiogenic factors?

Answer 42

angiogen
vascular endothelial growth factor
fibroblast growth factor
transforming growth factor

Question 43

how can we, pharmacologically, inhibit angiogensis?

Answer 43

with vascular endothelial growth factor inhibitors (VEGF)

Question 44

what are some common side effects of EGFR inhibitors?

Answer 44

papulopastular rash across face and torso
diarrhoea
nausea
vomiting
fatigue dehydration

Question 45

what are some common side effects of EGFR inhibitors?

Answer 45

papulopastular rash across face and torso
diarrhoea
nausea
vomiting
fatigue dehydration

Question 46

what are some side effects of immune checkpoint inhibitors e.g. PD-1 inhibitors?

Answer 46

◦ fatigue
	◦ nausea
	◦ loss of appetite
	◦ skin rash
	◦ itching

Question 47

what are some side effects of immune checkpoint inhibitors e.g. PD-1 inhibitors?

Answer 47

fatigue
	◦ nausea
	◦ loss of appetite
	◦ skin rash
	◦ itching

Question 48

what are some side effects of immune checkpoint inhibitors e.g. PD-1 inhibitors?

Answer 48

fatigue
nausea
 loss of appetite
skin rash
itching

Question 49

what are some common side effects of angiogenic inhibitors?

Answer 49

bleeding
increased bp
rash / itchy skin
diarrhoea
fatigue
 low blood counts