breast cancer : radiation therapy process

Question 1

Patient Positioning Difficulties
CT: APERTURE SIZE

Answer 1

-arm position - mobility post surgery and if it fits through the bore

-breast board tilt
-field of view - not encompass the whole breast

Question 2

Possible Positioning Uncertainties:
skin marks

Answer 2

-may shift TO DEEPER TISSUE
-the thickness in set up lines may cause variations in field position
-variation of remarking if faded

Question 3

Positioning Uncertainties:
internal motion - intrafractional

Answer 3

Respiratory
cardiac
changes in size and shape of organ

Question 4

techniques used to decrease mean heart dose

Answer 4

DIBH
prone RT
proton therapy

Question 5

Proton Therapy

Answer 5

lower exit dose due to the sharp dose gradient fall off