OARS

Question 1

Dose constraint Brachial plexus

Answer 1

Max dose ≤ 66Gy equivalent (EQD2)

(EviQ)

Question 2

Dose constraint:
Heart

Answer 2

Mean heart dose ≤ 20 Gy (EVIQ)
V40Gy <20% (WBCC constraint)

Outcome-OS

Question 3

Dose constraint:
Oesophagus

Answer 3

V60Gy ≤ 17%

Mean oesophageal dose ≤ 28 Gy

Question 4

What dose constraints are used to keep risk of grade 3 oesophagitis ≤ 10% ?

< 15%?

Answer 4

To keep risk of grade 3+ oesophagitis ≤ 10% aim for V60Gy ≤17%.

Mean oesophageal dose ≤ 28Gy for < 15% risk of grade 3 oesophagitis.

Question 5

Dose constraint :
Lung

Answer 5

Mean lung dose ≤ 20 Gy
V20Gy ≤ 35%
V5Gy ≤ 60%

Prioritise V20Gy constraints over achieving V5Gy constraints

Question 6

What dose constraints should be met to keep the risk of grade 2+ radiation pneumonitis
≤ 20%

Answer 6

mean lung dose ≤ 20Gy, V20Gy ≤ 35%,
V5Gy ≤ 60%.

Question 7

Should the GTV be included or subtracted in the lung contour?

Answer 7

4DCT: Volume both lungs and subtract iGTV

3DCT: Volume both lungs and subtract GTV

Or else high dose area is included within lung and increases the apparent mean dose to the lung.