Table 4.
Planning objectives and achieved dosimetric parameters for focal salvage brachytherapy delivered in a single fraction of 19 Gy.
| Planning objective | Median value (range) | % of plans that adhered to objectives | |
|---|---|---|---|
| Focal PTV Volume | 19.4 cm3 (8.5–43.0 cm3) |
||
| Focal-PTV D90% (Gy) | >17.1 Gy | 18.6 Gy (15.1–20.4 Gy) |
95% |
| Focal PTV V19Gy (%) | >90% | 88.5% (64.0–95.9%) |
35%* |
| Urethra D10% (Gy) (Hard constraint**) | <20.9 Gy | 16.96 Gy (6.3–20.8 Gy) |
100% |
| Rectum D2cm3 (Gy) | <12.35 Gy | 8.3 Gy (3.1–12.1 Gy) |
100% |
* Note clinical protocol limited coverage to hard constraint of the urethra.
** Soft constraint for Urethra D10% was <14.25 Gy for patients treated before 23/02/2015 (50% of patients met soft constraint) and <17.1 Gy for patients treated after 23/02/2015 (61% of patients met soft constraint).