Table 2.
Dose coverage of the breast-CTV and SIB-CTV and the in the planning CT compared and the estimated delivered dose distribution.
| Non-hypofractionated radiotherapy (n = 45) | Planning-CT | Estimated delivered dose distribution | ||
|---|---|---|---|---|
| Daily CBCT | EOD | Weekly | ||
| Breast-CTV | ||||
| Dmean | 51.4 ± 1.6 Gy | 49.9 ± 2 Gy | 49.8 ± 2.1 Gy | 49.7 ± 2.1 Gy |
|
Daily vs. EOD Δ − 0.1 (− 2.1; 0.7) Gy p = 0.06 |
Daily vs. Weekly Δ − 0.2 (− 2.3; 1.0) Gy p = 0.01 |
|||
| V95% | 85 ± 7.3% | 77.4 ± 8.9% | 77.1 ± 9.1% | 76.8 ± 9.2% |
|
Daily vs. EOD Δ − 0.3 (− 6.9; 1.6) % p = 0.13 |
Daily vs. Weekly Δ0.6 (− 7.3; 2.2) % p = 0.02 |
|||
| SIB-CTV | ||||
| Dmean | 61.8 ± 2.3 Gy | 61.8 ± 2.4 Gy | 61.5 ± 2.4 Gy | 61.4 ± 2.4 Gy |
|
Daily vs. EOD Δ − 0.3 (− 1.9; 0.5) Gy p < 0.01 |
Daily vs. Weekly Δ − 0.4 (− 2.1; 0.9) Gy p < 0.01 |
|||
| V95% | 98.6 ± 2.8% | 97.0 ± 4.7% | 96.1 ± 6.2% | 94.9 ± 7.6% |
|
Daily vs. EOD Δ0.9(10.9; 1.2)% p = 0.07 |
Daily vs. Weekly Δ2.1(− 20.1; 2.1)% p < 0.01 |
|||
| Hypofractionated radiotherapy (n = 5) | Planning-CT | Estimated delivered dose distribution | ||
|---|---|---|---|---|
| Breast-CTV | ||||
| Dmean | 40 ± 1.3 Gy | 39.4 ± 1.3 Gy | 39.4 ± 1.4 Gy | 39.4 ± 1.4 Gy |
| V95% | 89.2 ± 4.9% | 83.5 ± 3.6% | 83.4 ± 3.8% | 83.3 ± 3.8% |
| SIB-CTV | ||||
| Dmean | 47.2 ± 1.7 Gy | 47.5 ± 2.4 Gy | 47.5 ± 2.3 Gy | 47.5 ± 2.3 Gy |
| V95% | 99.8 ± 0.3% | 97 ± 5.5% | 96.9 ± 5.6% | 96.5 ± 6.3% |
Mean values and standard deviation. Mean absolute differences between CBCT-protocols (range).