Skip to main content

Table 1 Summary of the mean and one standard deviation of the dosimetric parameters obtained with PTV–based prescription

From: Optimizing the prescription isodose level in stereotactic volumetric-modulated arc radiotherapy of lung lesions as a potential for dose de-escalation

 

85% PIL

80% PIL

70% PIL

60% PIL

GTV D mean (Gy)

62.4 ± 1.5

66.2 ± 1.0

a74.4 ± 1.1

a84.2 ± 2.3

PTV D mean (Gy)

58.7 ± 0.9

60.6 ± 0.7

a63.9 ± 0.8

a67.3 ± 1.7

PTV D 98% (Gy)

53.6 ± 1.7

53.1 ± 0.2

a52.9 ± 0.2

a52.6 ± 0.4

Spinal cord D 1% (Gy)

9.1 ± 2.9

10.0 ± 3.9

9.7 ± 3.8

10.2 ± 3.5

Esophagus D 1% (Gy)

9.4 ± 3.6

9.6 ± 4.9

9.5 ± 5.2

9.6 ± 5.2

Bronchus D 1% (Gy)

13.6 ± 7.6

13.2 ± 7.6

12.6 ± 7.2

12.0 ± 7.2

Trachea D 1% (Gy)

5.3 ± 7.1

5.6 ± 7.4

5.1 ± 6.9

5.3 ± 7.3

Chest wall/Rib V30Gy (cc)

42.0 ± 35.7

34.7 ± 19.0

33.1 ± 22.1

30.2 ± 20.5

Heart D 1% (Gy)

10.7 ± 9.4

10.5 ± 9.3

10.0 ± 9.0

9.8 ± 8.7

PTV minus GTV D50% (Gy)

57.6 ± 0.7

59.2 ± 0.4

61.4 ± 0.8

63.5 ± 1.2

PTV minus GTV V54Gy (%)

34.5 ± 16.4

34.3 ± 16.2

34.2 ± 16.2

34.0 ± 15.9

Normal Lung MLD (Gy)

5.0 ± 1.7

4.7 ± 1.4

4.6 ± 1.3

4.6 ± 1.4

Normal Lung V30Gy (%)

4.9 ± 2.8

4.5 ± 2.0

4.1 ± 1.9

a4.0 ± 1.8

Normal Lung V20Gy (%)

8.4 ± 3.5

7.4 ± 3.0

7.1 ± 2.9

a7.0 ± 2.9

Normal Lung V10Gy (%)

13.9 ± 4.9

13.0 ± 4.1

a12.6 ± 3.6

a12.5 ± 3.8

Normal Lung V5Gy (%)

19.5 ± 4.9

19.2 ± 4.4

18.9 ± 4.2

18.8 ± 4.2

MU

4717 ± 994

a 4333 ± 868

4615 ± 1013

5011 ± 1031

nCI

1.08 ± 0.03

1.07 ± 0.02

1.07 ± 0.01

1.07 ± 0.01

R 50%

6.11 ± 1.42

5.73 ± 1.67

5.11 ± 1.26

a5.00 ± 1.07

  1. Abbreviations: GTV gross target volume, PTV planning target volume, D mean mean dose, D x% dose to x percent volume of the organ, V xGy percent volume of the organ receiving at least x Gy, MLD mean lung dose, MU monitor unit, nCI target dose conformity index, R 50% dose gradient index, PIL prescription isodose line relative to the maximum dose. aSignificant difference from the reference 85% PIL