(PM3B) Cancer Treatment

Question 1

What are the key aims of cancer treatment? List them in order of priority.

Answer 1

(1) Cure cancer
(2) Remission + mitigation – significant reduction in tumour size
(3) Symptomatic/ palliation – treatment of secondary complications + relief of symptoms
(4) Terminal care – improve quality of life + optimisation of symptom control

Question 2

What is the likelihood of curing a systemic cancer?

Answer 2

Depends on the type

Leukaemias are not solid tumours – can be highly sensitive to chemotherapy drugs

Question 3

What is palliation?

Answer 3

When cure is no longer possible

Question 4

What is the average life expectancy prolongation of solid tumours using current therapy?

Answer 4

2-18 months

Question 5

What is the average life expectancy prolongation of some leukaemias and lymphomas?

Answer 5

5-8 years

Question 6

What is the primary treatment of tumours?

Answer 6

Surgery – excision of primary tumour

Question 7

For which cancers is bone marrow transplantation appropriate?

Answer 7

Some leukaemias

Question 8

What are some common treatments available for cancer therapy?

Answer 8

(1) Surgery
(2) Bone marrow transplantation
(3) Radiotherapy
(4) Drugs –chemotherapy/ hormone therapy/ immunotherapy

Question 9

Which factors decide the appropriate treatment to use for cancer?

Answer 9

(1) Empirical clinical evidence

(2) Practical considerations

Question 10

What are some potential reasons for choosing surgery as a treatment for cancer?

Answer 10

(1) Well-defined solid tumour
(2) Non-vital regions
(3) Non-mutilating results
(4) Resection/ reconstruction possible

Question 11

Why may radiotherapy be selected for treatment of cancer?

Answer 11

(1) Diffuse but localised tumour
(2) Vital region/ organ
(3) Adjuvant therapy
(4) Palliation – reducing symptoms

Question 12

What are some potential reasons for selecting chemotherapy as a treatment for cancer?

Answer 12

(1) Adjuvant therapy
(2) Neo-adjuvant therapy (prior to surgery)
(3) Widely disseminated/ metastasised
(4) Diffuse tumour
(5) Palliation – reducing symptoms
(6) Some primary tumours (e.g. Hodgkin’s lymphoma)

Question 13

How do chemotherapeutic agents work?

Answer 13

Kill cells that are rapidly dividing

NOT tumour specific

affect hair follicles + gastrointestinal mucosa

Question 14

What is radiotherapy?

Answer 14

Sending x-rays into the body

Ionisation of certain cells within the body

Question 15

Why is chemotherapy used?

Answer 15

Most commonly used to treat advanced cancer

Trying to reduce volume of the tumour

Question 16

What is a downside of chemotherapy, relating to tumour progression?

Answer 16

By the time a tumour is observable

Their growth has slowed

Less susceptible to chemotherapy

Question 17

Why are a combination of chemotherapy drugs often given in treatment?

Answer 17

To achieve a high therapeutic effect

With minimal overlap of toxicity

Question 18

What type of chemotherapy drugs are preferable?

Answer 18

(1) Drugs with known synergistic killing effects
- e.g. platinum drugs + 6-fluorouracil

(2) Combination of drugs that kill cancer at different stages of the cell cycle

Question 19

Which stage of the cell cycle do microtubule inhibitors act on?

Answer 19

GAP 2 (G2) Phase

Question 20

Which stage of the cell cycle do antimetabolites act on?

Answer 20

GAP 1 (G1) Phase

Question 21

What are some of the side effects of cytotoxic chemotherapy?

Answer 21

(1) Myelosuppression – rapid falls in peripheral blood count
(2) GIT + Bladder – erosion/ ulceration
(3) Fertility – spermatogenesis is inhibited
(4) Teratogenic activity –during organogenesis
(5) Hair loss
(6) Genetic damage – heritable defects may be caused if DNA of ova/ spermatazoa are mutated
(7) Carcinogenesis – as well as curing cancer, can also cause cancer (same as radiotherapy)
(8) Nausea + vomiting – direct stimulation of the chemoreceptor trigger zone

Question 22

What are some ways that side effects of chemotherapy may be managed?

Answer 22

(1) Anti-emetics
(2) Full blood counts
(3) Enhancement of bone marrow proliferation
(4) Forced diuresis – slight over hydration followed by a diuretic to increase urinary output

Question 23

How can myelosuppresion in chemotherapy be minimised?

Answer 23

(1) Blood transfusions
(2) Growth factors
(3) Timing of doses
(4) Careful monitoring
(5) Isolation in sterile environment

Question 24

How may nausea and vomiting as a result of chemotherapy be minimised?

Answer 24

Antiemetics

Question 25

What is a complete response to cancer treatment?

Answer 25

Complete disappearance of all signs of disease

Question 26

What is a partial response to cancer treatment?

Answer 26

More than 50% reduction

Question 27

What is considered a stable disease in cancer?

Answer 27

Less than a 50% reduction

Less than a 25% increase

Question 28

What is considered progressive cancer?

Answer 28

Increase of tumour size by at least 25%