ESTRO 2025 - Abstract Book

S2117

Clinical - Urology

ESTRO 2025

No ≥ grade 3 was observed. Figure 1a shows the small increase in grade 2 GU toxicity during treatment, with a reduction three months after treatment. A similar increase during treatment was seen in patient reported symptoms, with a smaller or no reduction at three months follow-up (Figure 1b).

Conclusion: This trial shows that a PTV-margin of 5mm is sufficient to cover the SV when combining online adaptation with intra fraction fiducial tracking and should be considered a successful first step towards ultra-hypofractionation for high risk PCa patients with the entire SV in the target volume. The treatment was well-tolerated.

Keywords: Online-adaptive, Seminal vesicles, SBRT

References: [1] Parker CC, James ND, Brawley CD, Clarke NW, Hoyle AP, Ali A, et al. Radiotherapy to the primary tumour for newly diagnosed, metastatic prostate cancer (STAMPEDE): a randomised controlled phase 3 trial. Lancet. 2018;392:2353-66.