Table 2 The constraints evaluation of ipsilateral lung, contralateral breast and heart of all plans stratified by different breast sizes. L large breast size (n = 18), M medium breast size (n = 52), S small breast size (n = 29)

 V_16Gy[%]

12.9 ± 3.8

14.5 ± 3.6

13.7 ± 3.5

0.25

13.0 ± 3.5

13.5 ± 3.3

13.1 ± 2.2

0.78

 V_4Gy[%]

28.1 ± 6.9

29.7 ± 5.8

25.7 ± 3.7

< 0.01

28.8 ± 7.0

28.4 ± 5.2

26.8 ± 2.4

0.30

 V_5Gy[%]

0.0 ± 0.0

0.3 ± 1.7

0.0 ± 0.4

0.46

0.0 ± 0.0

0.8 ± 3.4

0.0 ± 0.0

0.23

 Max[Gy]

2.0 ± 2.3

4.7 ± 9.6

2.2 ± 2.6

0.19

3.6 ± 4.4

6.6 ± 11.3

2.8 ± 2.9

0.13

 V_20Gy[%]

0.9 ± 1.4

0.9 ± 1.3

0.9 ± 1.2

0.98

1.2 ± 1.5

0.9 ± 0.9

0.9 ± 1.1

0.42

 Mean[Gy]

1.5 ± 0.6

1.4 ± 0.6

1.3 ± 0.7

0.37

1.7 ± 0.7

1.4 ± 0.5

1.2 ± 0.5

0.03