Radiotherapy

Question 1

What are the varying strengths of radiation?

Answer 1

Alpha-weakest
Beta- middle
Gamma- strongest.

Question 2

Define radiotherapy.

Answer 2

The treatment of disease by ionising radiation.
Causes apoptosis- forms free radicals which do further damage.
Used in the treatment of malignancies.

Question 3

What is an advantage to ionising radiation?

Answer 3

Targeted to damaged cells, healthy cells recover.

Question 4

What type of radiation is more commonly used to treat malignancies?

Answer 4

Alpha and gamma are the radiation of choice. They are the most effective at producing ionisation.

Question 5

List examples of when radiotherapy may be used.

Answer 5

To treat cancer as a stand alone treatment.
To shrink a tumour before surgery.
Reduce cancer after surgery.
Control the symptoms or reduce pain.
Reduce the growth of cells- Graves disease.

Question 6

Explain external radiation.

Answer 6

Supplied from outside the body.
Administered over several days or weeks.
Mark a targeted area so a patient must lie motionless.
A painless procedure that only lasts 5 mins.

Question 7

Explain conformal radiotherapy.

Answer 7

3D use of metal blocks to direct the beam of ionising radiation.
Effective ar more closely targeting the shape of a tumour.
Used for prostate cancer.

Question 8

Explain internal radiation.

Answer 8

Known as brachytherapy.
Given once or a few times- usually involves a short stay in hospital.
Made up of radioactive wires and seeds of gold or iodine.

Question 9

How is internal radiotherapy monitored?

Answer 9

Geiger counter

Question 10

List examples of internal radiotherapy

Answer 10

Strontium 89 and Samarium 153 for bone cancer.
Iodine 131 for thyroid gland.
Radium 223- for secondary bone cancer trials.

Question 11

Explain the side effects of radiotherapy.

Answer 11

Effects depend on the area being treated, dose of radiation, physical wellbeing at the time of treatment.
Side effects can appear during treatment or weeks/months after treatment

Question 12

Explain the side effects of tiredness.

Answer 12

Can be caused by physical exertion of going to treatment everyday.
Anaemia- the destruction of erythrocytes.
Less 02 carrying capacity.
In extreme cases a transfusion may be required.
Bone marrow affected.
Diarrhoea.

Question 13

Explain the symptoms for nausea and sickness.

Answer 13

Depends on area being treated- e.g GI tract and brain.
Can feel sick during and post treatment.
Diet is altered.
Loss of appetite.

Question 14

Explain infertility.

Answer 14

Loss of libido (tiredness)
Early menopause
Prostate impotence.

Question 15

Explain radiotherapy and thyroid gland.

Answer 15

Used to treat hyperthyroidism- graves disease.
Reduces the activity of the thyroid gland.
Less T3/T4 is released.

Question 16

Explain hyper fractionated radiotherapy.

Answer 16

Increased frequency of fractions- more than once a day.
Treatment is given over 12 days rather than 4-6 weeks.
Total dose is the same but requires a stay in hospital.

Question 17

Explain hypo fractionated radiotherapy.

Answer 17

Increase dose of radiotherapy per fraction at a lower frequency of fractions.
Reduces the side effects and reduces risk of cancer.

Question 18

Explain stereotactic radiotherapy.

Answer 18

Treatment used to treat small round tumours found in the head. 
Used to treat pituitary adenomas
Acoustic neuromas.
Meningiomas
Gliomas

Question 19

Explain sterotactic radiotherapy.

Answer 19

Patients receive a single dose of radiation.
May be used in patients that can’t undergo surgery.
Damages nerves so therefore can’t be used for medium and large tumours.
IMRT and IGRT.