Table 2 Summary comparison of VMAT and HT plans

PTV

D_V95% (Gy)

49.3 ± 0.1

49.8 ± 0.1

<0.001

DHI

0.147 ± 0.009

0.096 ± 0.005

<0.001

CI

0.778 ± 0.008

0.719 ± 0.008

<0.001

TCP

99.8 ± 0.2

100 ± 0.0

0.002

Total lung

V_5Gy (%)

66.2 ± 3.1

89.8 ± 1.4

<0.001

V_20Gy (%)

16.3 ± 0.2

15.0 ± 0.3

<0.001

NTCP (%)

0.3 ± 0.1

0.6 ± 0.1

0.06

SCCP (%)

5.3 ± 0.1

6.1 ± 0.0**

<0.001

Ipsilateral lung

V_5Gy (%)

96.9 ± 1.3

99.3 ± 0.5

0.06

V_20Gy (%)

32.3 ± 0.8

29.9 ± 1.0

<0.001

Contralateral lung

V_5Gy (%)

37.8 ± 4.9

81.7 ± 2.5

<0.001

Heart*

V_15Gy (%)

26.0 ± 1.9

28.2 ± 2.6

0.4

D_mean (Gy)

12.9 ± 0.5

14.4 ± 0.6

0.04

D_max (Gy)

42.2 ± 1.6

38.3 ± 1.3

<0.001

NTCP (%)

1.3 ± 0.2

0.9 ± 0.1

0.008

Contralateral breast

Mean dose (Gy)

1.5 ± 0.1

1.8 ± 0.1

<0.001

SCCP (%)

1.0 ± 0.0**

1.2 ± 0.0**

<0.001

Non-specific normal tissue

Mean dose (Gy)

7.0 ± 0.2

11.1 ± 0.4

<0.001

SCCP (%)

0.7 ± 0.0

0.9 ± 0.0**

<0.001

Efficiency

Delivery time (s)

128.6 ± 2.8

382.4 ± 10.9

<0.001