Table 3 The summary of the coverage study. SFRT_1 A: dose normalisation to the maximum dose tolerable for PTV2mm (maximum D90%). SFRT_1 B: plan reoptimized and normalised as in A. In both A and B subset the maximum D90% was determined as the value preventing any constraint violation in the OARs. In the objective’s column, the values in brackets correspond to the upper har limit for the corresponding metrics. The ranges are reported in square brackets
| Structure | Parameter | Objective | SFRT_1 | SFRT_1 A | SFRT_1 B |
|---|---|---|---|---|---|
| CTV | D90% | 30 Gy | 30 |
35.3 ± 3.2 [30.3,38.2] |
33.1 ± 2.5 [30.1,37.9] |
| V45Gy | ≥ 50–55% |
43.1 ± 7.5 [33.0,55.9] |
61.3 ± 13.9 [35.3,77.4] |
51.6 ± 13.8 [36.4,76.4] | |
| V60Gy | ≥ 30% |
15.4 ± 5.6 [6.9,23.9] |
29.2 ± 13.0 [7.2,47.1] |
18.7 ± 11.0 [5.4,43.4] | |
| PTV2mm | D90% | 30 Gy |
23.2 ± 1.3 [21.0,24.5] |
27.2 ± 2.8 [22.3,30.6] |
28.2 ± 1.8 [25.1,] |
| PTV5mm | D90% | 30 Gy |
20.0 ± 1.4 [19.0,21.8] |
23.5 ± 2.8 [20.1,27.4] |
25.1 ± 1.6 [22.1,26.8] |
| Bladder | D2cm3 | < 23.75 (27.5) Gy |
22.4 ± 2.0 [20.2,27.0] |
26.2 ± 1.7 [23.0,27.4] |
26.1 ± 1.3 [24.2,27.4] |
| Rectum | D2cm3 | < 17.0 (19.45) Gy |
13.9 ± 2.9 [11.2,19.6] |
16.2 ± 2.9 [10.4,20.6] |
18.6 ± 0.8 [16.9,19.4] |
| Sigmoid | D2cm3 | < 19.5 (21.65) Gy |
2.6 ± 3.1 [0.5,10.4] |
3.0 ± 3.1 [0.6,10.5] |
5.3 ± 6.3 [0.6,18.7] |
| Bowel | D2cm3 | < 17.0 (19.45) Gy |
9.1 ± 5.9 [1.2,17.6] |
10.5 ± 6.8 [1.5,19.9] |
10.2 ± 6.2 [1.4,17.2] |