Radiotherapy Flashcards
What is radiation?
Atoms - made up of neutrons protons and electrons.
What are the different types of ionising radiation?
Electromagnetic waves - x-rays or gamma rays. Alpha or A particles. Beta or B particles.
What is radiotherapy?
The treatment of disease by ionising radiation.
How does radiotherapy work?
Penetrates tissues and alters the nuclear material e.g DNA disrupting cell growth. Damagin cells causes apoptosis - forming free radicals causing further damage to the cells.
What are the types of radiation more commonly used for treating malignancies?
Alpha and gamma radiation - as they are more likely to cause tissue or cell damage as they are more effective at producing ionisation.
When is radiotherapy used?
To treat cancer as a stand alone treatment. To shrink a tumour before surgery. To reduce cancer returning after surgery. To control symptoms or to reduce pain. To reduce the growth of cells.
Which specific malignancies does radiotherapy treat?
Brain, skin, prostate, uterus, breast.
What are the 2 types of radiotherapy?
External and Internal.
What happens in external radiotherapy?
Usually given over several days or weeks. Mark target area - need to lie in a certain position, motionless. Painless procedure. Uses a radiotherapy machine - emits high energy x-rays.
What is Conformal radiotherapy?
3D CRT - use of metal blocks to direct the beam of ionising radiation. More closely targets the shape of the tumour. Used in prostate cancer.
What happens in internal radiotherapy?
May be given once or only few times. Usually involves a short stay in hospital. Radioactive wires or seeds put into affected area. May also be given IV or in liquid form.
What are the different types of internal radiotherapy?
Strontium 89 and Samarium 153 - some bone cancers.
Iodine 131 - thyroid gland.
Radium 223 - secondary bone cancer.
What are the side effects of radiotherapy?
Dependant on area being treated and dose of radiation and physical well being at time of treatment.
Tiredness…
Physical exertion of going for treatment every day. Anaemia from destruction of erythrocytes. Less oxygen carrying capacity. Bone marrow affected
Nausea and sickness…
Gi, brain treatments. Alter diet. Prescribe anti-emetics.
