The Role of the Radiation Therapist

Question 1

What is RadioTherapy? What is its aim?

Answer 1

Treatment of cancer with ionising Radiation

1) kill tumour cells before they spread
2) reduce sizes of tumours to help symptoms

Question 2

What are the ways we can treat cancer?

Answer 2

surgery, chemotherapy, hormone therapy, immunotherapy

Question 3

What does EMR stand for?

Answer 3

electromagnetic radiation

Question 4

What is immunotherapy?

Answer 4

We can place monoclonal antibodies into the patient. Essentially antibodies are grown and harvested from another organism (such as a mouse) these are then placed into the human to fight the cancer

Question 5

What three factors can exacerbate cancer growth?

Answer 5

Smoking, alcohol, radiation, genes,

Question 6

Why do we surgically remove tumours?

Answer 6

surgical removal before they compress other structures

Question 7

How can cancer spread?

Answer 7

Tumours spread via lympatic and blood drainage systems

Question 8

Once cancer has spread via blood drainage and/or lymphatic systems, what type of treatment does the patient need?

Answer 8

Systematic (chemotherapy)

Question 9

What are other forms of radiation besides IR?

Answer 9

Atmospherical radiation, phones EMR

Question 10

If a drug ends in MAB?

Answer 10

These are all monoclonal antibodies

Question 11

What is Palliative radiotherapy?

Answer 11

Aims to improve the quality of life by relieving symptoms without causing unacceptable side effects
delivering lower doses in smaller fractions (can be high dose with lung)

Question 12

What type of patients is palliative radiotherapy good for?

Answer 12

Patients with metastic disease

Question 13

What are examples of palliative prescriptions?

Answer 13

30 gray in 10 fractions, 25 gray in 5 fractions, 35 gray in 12 fractions

Question 14

What is the reason for palliative prescriptions?

Answer 14

We want to reduce the amount of time spent at the clinic and reduce their pain, (really good with bone cancer)

Question 15

How does radiotherapy work?

Answer 15

Ionisation damages DNA or ionises water into more damaging chemical (free radical) which damages DNA

Question 16

Why wouldn’t you recommend antioxidants during treatment?

Answer 16

They can repair the cancer genes

Question 17

How is radiotherapy produced?

Answer 17

accelerating an electron into a block of metal, more acceleration produdes more energy

Question 18

What are the benefits of old cobalt machines? Why are they still in use? (rarely)

Answer 18

3rd world countries, that don’t have access to reliable electricity, tropical countries during storms
They do produce good dose

Question 19

Why and what type of kilovoltage (kV) is used?

Answer 19

• up to 300kV

- penetrates body most dose at the surface (treats superficial)

Question 20

Why is Megavoltage (MeV or MV) used?

Answer 20

• 4MeV to 20 MeV
• deposit high dose at depth
• used to treat tumours that are centralised- middle of the body

Question 21

What energy is usually used for head and neck?

Answer 21

4MV

Question 22

Energy for thorax?

Answer 22

6MV

Question 23

energy Pelvis?

Answer 23

10MV or 18MV (QLD doesn’t use 18MV, need proton doors)

Question 24

What is brachytherapy?

Answer 24

Inserting radioactive source interstially intra-cavity (internal opening cavity of human), stay in patient and deliver dose over time

Question 25

What is brachytherapy?

Answer 25

Inserting radioactive source interstitially intra-cavity (internal opening cavity of human), stay in patient and deliver dose over time

Question 26

What does a radiation therapist do?

Answer 26

- Plans radiation therapy - delivers radiation therapy - provides support and care - provides advice about radiotherapy - Education and research - major role in multi-disciplinary team - advocates for the patient

Question 27

What is the usual patient pathway? (prescription)

Answer 27

- Radiation oncologist councils patients on benefits and negatives of different treatments - decides on optimal treatment, and prescribes dose energy and overall timing of course - patient booked for MI

Question 28

What is the usual patient pathway? (prescription)

Answer 28

- Radiation oncologist councils patients on benefits and negatives of different treatments - decides on optimal treatment, and prescribes dose energy and overall timing of course - patient booked for MI

Question 29

What are important conversations the RT needs to have with the patient on Sim?

Answer 29

Discuss possibility of time lengthen of planned treatment, due to public holidays machine breakdown etc

Question 30

Patient pathway- localisation?

Answer 30

- involves CT scan, very few use x-rays - RT performs scan - images used to identify tumour, OAR

Question 31

How much extra of the patient do we need to CT scan if we scan a lung tumour patient?

Answer 31

scan from the chin to amout 5cm inferior to lung We need to scan the entire lung because we need to know entire dose to the normal tissue and lung

Question 32

Patient Pathway- planning, what is involved?

Answer 32

RT uses specialist software to illustrate the dose distribution in the patient for different combinations of beams - imaging - dose planning + calculation - how to direct IR to tumour - ensure minimal OAR dose - ensure critical structures are safe

Question 33

What is the 'therapeutic ratio' why is it important?

Answer 33

consider theraputic ration- Possibility of tumour control, vs possibility of damage to OAR

Question 34

What is FDG? (used in PET)

Answer 34

Flurodeoxyglycose It is an glucose solution that is a radioactive trace. This is injected into the patient, has a half life of usually half an hour. Since tumours use up a lot of energy due to high cell cycle, it accumulates in the cancerous tissues.

Question 35

What are the problems with MR?

Answer 35

- Patients can be claustrophobic | - patients with certain metallic implants possibly can't have MR

Question 36

Patient pathway- treatment, what is involved?

Answer 36

The RT must explain the process and potential side effects, need to explain who you are what you are doing. ESPECIALLY during straighten and level - Need to position accurately the same way each day - leave the room, ring the bell, communicate to patient and beam on - patient observed by CCTV

Question 37

What is a typical time for patient treatment?

Answer 37

10-15 mins | 5-8 weeks

Question 38

Patient pathway- side effects experienced? how is the RT involved?

Answer 38

Apart from fatigue- erythema, temporary hair loss, diarrhoea, nausea, frequency of urination