ESTRO 2024 - Abstract Book

S2342

Clinical - Urology

ESTRO 2024

Eligible patients (prostate cancer meeting PACE B eligibility criteria; T2 N0 M0, max Gleason 3+4, IPSA<20) were treated using lin-acc based prostate SABR. Androgen deprivation therapy was used at clinician discretion. All patients had 3 fiducial markers inserted prior to radiotherapy planning. Rectal spacer was permitted at clinician discretion as it became locally available in April 2021. CT and MR simulation were obtained with standard bowel and bladder preparation. Planning images were fused prioritising fiducial marker match. CTVs, PTVs and OARs were contoured adhering to the PACE B radiotherapy guidelines, and all contours were peer-reviewed prior to radiotherapy planning. Prescription was 3625cGy in 5 fractions alternate days over 2 weeks, with PTV and OAR constraints as per PACE B. Image guidance was with daily seed match and CBCT soft tissue match. Patients were assessed weekly during and shortly after completion of radiotherapy using CTCAEv5 toxicity scoring. Patients were assessed at week 4 post radiotherapy, at 2 months and thereafter 3- to 6-monthly at clinician discretion.

Results:

90 patients were treated with prostate SABR from December 2020 to September 2023 and are available for analysis. Baseline characteristics are presented in table 1. Median age was 66, range 51-84 years. 85 patients had clinical T2 N0 M0 disease, the remainder had T1c disease. Median PSA at presentation was 8.0ng/ml range 2.9-18.1ng/ml. 38 patients had Gleason 6 disease and 52 had Gleason 7, 3+4 disease. All patients had Cambridge Prognostic Group 1 or 2 disease.