ESTRO 2025 - Abstract Book

S1959

Clinical - Urology

ESTRO 2025

Material/Methods: Prospective series of 60 Pca of high-very high risk group (NCCN) were included. Baseline sexual function assessed using Expanded Prostate Cancer Index Composite for Clinical Practice (EPIC ‐ CP) questionnaire for sexual symptoms score. Patients received ADT as per risk categorisation. Radical SBRT consisted of 36.25Gy in 5 fractions (Pelvic nodal 25 Gy in 5 fractions) with Linac based standard protocol on alternate days or weekly. Mean Dose to PB and bilateral NVB were documented. Sexual function by EPIC-CP monitored at baseline and then 6 monthly till last follow up. Results: With median age of 61 years, 80% (48) patients belong to NCCN high risk and 20% (12) very high-risk categories. Median follow up was 20 months (range, 12 – 45 months). All patients received elective pelvic nodal radiotherapy. Mean dose range to PB was 9.5-29.4Gy. NVB Dose ranged from V34.4 (83.3% - 91.8%), V32 (94.5-99.16%) V28(99.76 100%). The EPIC ‐ CP for sexual symptoms score reported (out of 12) median score at baseline of 3 (range2-4), at 6 months 4.5 (range3-6)), at 12 months 5 (range 3-7), at 24 months 5.5 (range 4-7) and at 30 months 7 (range 6-8 The higher score represented worsening sexual function QOL. Till last follow up 57 patients were biochemically controlled and both median and mean score of EPIC-CP sexual domain declined over follow up period. The other side effects were within acceptable limit. The sexual QOL reduction implicated clinical effect of ADT and dose received to PB and NVB. Few patients beyond 3 years of follow up reported some recovery in EPIC-CP score in sexual function domain. Conclusion: A substantial group of patients in our study had mild or no erectile dysfunction at base-line but compromised sexual health after ADT and SBRT. The technical challenge of sparing NVB for high-very high risk Pca combined with effect of ADT remains a concern. The limitations in documentation of sexual QOL by EPIC-CP and poor acceptance due to multitude of reasons, non-dosimetric factors for sexual QOL decline are future challenges. Future prospective documentation and pragmatic sparing of NVB with indigenous sexual QOL can highlight specific issues in prospective manner.

Keywords: prostate SBRT, sexual QOL, ADT, NVB

References: 10.1016/j.ijrobp.2023.12.037

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Proffered Paper Is hypofractionated whole-pelvis RT (WPRT) as well tolerated as conventional WPRT in prostate cancer? Analysis of the Hope trial primary endpoint Lucas C Mendez 1 , Juanita Crook 2 , Kevin Martell 3 , Vikram Velker 1 , Belal Ahmad 1 , Michael Lock 1 , Aneesh Dhar 4 , Ross Halperin 5 , Bryan Schaly 6 , Douglas A Hoover 6 , Andrew Warner 1 , Glenn S Bauman 1 , David P D'Souza 1 1 Radiation oncology, London Heath Sciences Centre, London, Canada. 2 Radiation, BCCancer, Kelowna, Canada. 3 Radiation oncology, Tom Baker, Calgary, Canada. 4 Radiation oncology, Lonrydon Heath Sciences Centre, London, Canada. 5 Radiation oncology, BCCancer, Kelowna, Canada. 6 Medical Physics, London Heath Sciences Centre, London, Canada Purpose/Objective: Stereotactic ablative radiotherapy is a standard of care option for men with high probability of prostate cancer confined to the prostate. However, the role of ultra-hypofractionated (UH) WPRT is not well defined in prostate cancer patients. This trial investigates the role of UH WPRT following HDR brachytherapy and hypothesizes that UH WPRT is non-inferior to conventionally-fractionated WPRT in terms of late bowel scores.