Principles of Cancer Treatment

Question 1

If cancer is localised, what would the treatment option be?

Answer 1

Surgical removal of the primary cancer accompanies by additional drug or radiation treatment to kill residual cancer

Question 2

What is the objective of cancer treatment?

Answer 2

To maximize the effects on cancer while minimizing the side effects on normal cells

Question 3

What kind of cancers are not suitable for surgery?

Answer 3

Cancers of blood cells, leukaemia´s
Solid cancers that have metastasised to inaccessible sites like bone and brain

Question 4

What is the Cytostatic effect?

Answer 4

Prevention of cell proliferation
-prevents growth but doesn’t eliminate cancer

Question 5

What is the cytotoxic effect?
-potential to cure a patient

Answer 5

The killing of cancer cells

Question 6

What can be used specifically to treat major cancers like prostate and breast?

Answer 6

Hormone treatments

Question 7

What is metastasis?

Answer 7

A process specific to cancers and has its own control mechanisms which include angiogenesis

Question 8

What does prognosis mean?

Answer 8

The likely duture behaviour of a cancer and can also determine the likely outcome for the patient

Question 9

What are prognostic factors in relation to cancer?

Answer 9

Clinical features such as tumour size or tumour spread and specific biochemical markérs or tumour markers in tissue or blood associated with the tumour

Question 10

What does Remission mean?

Answer 10

A decline in cancer size as a result of treatment

Question 11

What does relapse mean?

Answer 11

The reappearance of a cancer

Question 12

How can cancer cells be prevented from being generated? What is an example of this

Answer 12

By using vaccination
Cervical cancer vaccine - vaccine against the Human Papilloma virus which is the causative agent for cervical cancer

Question 13

What are the definitions that are applied to cancers responses to treatment and what do they mean?

Answer 13

–When a cancer disappears completely - complete repsonse
–Partially removed/some remains - partial response
–Remains static - no change
–Continues to grow - progressive disease

Question 14

What are the 2 criteria used in defining cancer?

Answer 14

1. Tumour size and the degree of spread- STAGE of disease
2. Cellular characteristics of the cancer- GRADE

Question 15

What criteria is staging based on?

Answer 15

TNM system
1. Tumour size
2. Spread to lymph Nodes
3. Metastasis to distant sites

Question 16

Difference between a Stage 1 cancer and a Stage 4 cancer

Answer 16

A Stage 1 cancer is one of small size that has not progressed outside its original state whereas a stage 4 growth is large and has spread widely to other parts of the body

Question 17

Differences between low grade and high grade tumour

Answer 17

A low grade tumour has histological resemblance to the tissue of origin whereas a high grade cancer has undergone so many changes that it only marginally resembles the tissue of origin

Question 18

Criteria for grading a tumour

Answer 18

Number of mitoses, irregularities in nuclear shape, and relative architectural resemblance to normal tissue

Question 19

Why does early detection of cancer mean better results?

Answer 19

The earlier a cancer is detected the fewer chnages it has undergone and the more likelihood there will be of getting a good response to treatment

Question 20

How does Radiotherapy work?

Answer 20

Radiation such as X rays damage DNA and may kill the cancer cells
DNA can be irreversibly damaged by ionizing radiation such as x rays - can affect healthy tissue too

Question 21

How can the effect of damging healthy cells be minimised in radiation therapy?

Answer 21

By fine focusing of radiation onto the cancer
By dividing the total dose into several fractions given over several weeks

Question 22

What kind of drugs is the name ‘chemotherapy’ given to and what kind of cells do these drugs best effect? Whhat does its efficiency depend onß

Answer 22

Drugs whose actions are largely based on blocking cell proliferation
Most effective against rapidly dividing cells
Efficiency depends on concentration of the drug reaching the tumour and duration of this exposure

Question 23

How can side effects of chemotherapy be minimised?

Answer 23

By using a combination of drugs with different toxicities

Question 24

What does Primary Chemotherapy mean?

Answer 24

Describes its use as a first line of treatment for local disease

Question 25

What does Adjuvant Chemotherapy mean?

Answer 25

When the agent is used in addition to ther treatments (surgery) to kill cancer cells

Question 26

What is a mutagen?

Answer 26

Agent that changes the genetic material, usually DNA e.g chempotherapeutic agents

Question 27

What type of cancer do patients who receive chemo have an increased risk of getting?

Answer 27

Leukaemia as chemo damages DNA

Question 28

What does chemotherapy do?

Answer 28

Directed at disrupting the cell cycle with DNA, RNA and proetins being the targets

Question 29

What are the 3 categories of synthetic chemotherapeutic agents in curent use?

Answer 29

1. Whether they alkylate DNA (alkylating agents transfer and alkyl group from one molecule to another)
2. Anatgonise mtabolites needed for DNA synthesis (antimetabolites)
3. Natural products from plants and fungi

Question 30

Example of an Alkylating agent, the processes it affects and the cancers it treats

Answer 30

Cyclophosphamide
Affects DNA synthesis
Treats breast cancer and leukaemia

Question 31

Example of an antimetabolite agent, the process it affects and the cancers it treats

Answer 31

Methotrexate
Affects dihydrofolate reductase
Treats breast cancer and placenta cancer

Question 32

Example of natural products, the processes it affcets and the cancers it treats

Answer 32

Doxorubicin
Affects DNA and RNA synthesis
Treats lung, breast cancer and leukaemia

Question 33

Side effects of chemotherapy?

Answer 33

Anaemia, Thrombocytopenia, Neutropenia (haemopoietic cells in bone marrow are particularly sensitive to many chemo drugs)
Destruction of immune cells make patient prone to infection
Hair loss as hair follicles are rapidly dividing cells
Nausea and vomiting - treat with anti emetic drugs

Question 34

What is hormone therapy?

Answer 34

A treatment that uses medicines to block or lower the amount of hormones in the body to slow down por stop the growth of cancer

Prevents excess steroid synthesis or blocks the effects at the target cell via the receptor machinery

E.g Tamoxifen to treat breast cancer or anti adrogens therapy to treat Prostatic cancer

Question 35

New treatments - angiogenesis

Answer 35

Treatment prevents new blood vessel formation in cancers and tissue invasion

Question 36

New treatments - Immunotherapy

Answer 36

Mechanisms that use or manipulate the immune system to facilitate the attack and lyse of tumour cells

Question 37

New treatments - Tyrosine Kinase Inhibitors

Answer 37

Treatments that attampt to interfere with the enzymes and proteins involved in cell signalling pathways controlling cell proliferation

Question 38

New treatment - what monoclonal antibody is used to treat some breast cancers?

Answer 38

Herceptin

Question 39

How does monoclonal antibody herceptin work?

Answer 39

Targets the Her 2 proteins / receptors which is present on cancer cells.
The Her 2 proteins stimulate cell proliferation.
The monoclonal antibody Herceptin binds to the Her 2 protein/receptor and interferes with cell signalling pathways and retard cell proliferation.