ESTRO 2024 - Abstract Book

S2354

Clinical - Urology

ESTRO 2024

sexual function, a decline was observed in 13% of patients in the EPIC-CP sexual domain and 26% in the IIIEF 5. Analyzing the overall QoL outcome a clinical worsening was identified in 9% of patients.

Paired t-test comparing pre-treatment and post-treatment questionnaire scores showed no statistically significant differences (P > 0.05).

Univariate analysis showed a significant association between higher rectum and bladder doses and late grade 1 GU toxicities: rectum mean dose (OR, 1.391; 95% CI, 1.048-1.848, P=0.022), rectum wall D50% (OR, 1.322; 95% CI, 1.049 1.666, P=0.018), bladder mean dose (OR, 1.395; 95% CI, 1.106-1.759, P=0.005), bladder wall D10cc (OR, 1.181; 95% CI, 1.057-1.321, P=0.003), bladder wall D25% (OR, 1.161; 95% CI, 1.037-1.300, P=0.009), and bladder wall D50% (OR, 1.265; 95% CI, 1.071-1.495, P=0.006). Conversely, univariate analysis did not find any factors significantly associated with the worsening of any domain based on the ICIQ-SF and EPIC-CP questionnaires (P>0.05). A significant correlation was observed between the decline in erectile function and the dose received by 2% of the PTV (OR, 2.560; 95% CI, 1.186-4.335; P=0.032). In multivariate analysis, only bladder wall D10cc (OR, 1.250, 95% CI, 1.017-1.537, P=0.034) independently correlated with late G1 GU toxicity incidence.

Conclusion:

Our findings demonstrate that post-prostatectomy SBRT does not increase toxicity or substantially worsen QoL. This suggests that SBRT can be safely employed in postoperative setting. However, further research with extended follow-up and randomized comparisons to various radiation schedules is encouraged.

Keywords: prostate cancer; salvage RT; SBRT.

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Poster Discussion

Baseline analysis of Q-ABC- prospective study comparing radiotherapy and surgery for bladder cancer

Ashok DB Nikapota 1 , Stephen Bremner 2 , Sue Catt 3 , Ananya Choudhury 4 , Isobelle Coombes 5 , Jo Cresswell 6 , Heather Gage 7 , Duncan C Gilbert 1 , Ruth M Habibi 3 , Peter J Hoskin 4 , Chris I Jones 2 , Gaurav Kapur 8 , Shirley F May 3 , Yvonne Rimmer 9 , Angus J Robinson 1 , Isabel Syndikus 10 , Morro Touray 7 , Mohini Varughese 11 , Sally Appleyard 1 1 UHSussex NHS Foundation Trust, Sussex Cancer Centre, Brighton, United Kingdom. 2 Brighton and Sussex Medical School, Dept of Primary care and Public Health, Brighton, United Kingdom. 3 Brighton and Sussex Medical School, Sussex Health Outcomes Research & Education in Cancer (SHORE-C), Brighton, United Kingdom. 4 The Christie NHS Foundation Trust, Department on Radiotherapy, Manchester, United Kingdom. 5 UHSussex NHS Foundation Trust, Clinical Investigation and Research Unit, Brighton, United Kingdom. 6 South Tees Hospitals NHS Foundation Trust, Department on Urology, Middlesborough, United Kingdom. 7 University of Surrey, Faculty of Health and Medical Sciences, Guildford, United Kingdom. 8 Norfolk and Norwich University Hospital Foundation Trust, Department on Radiotherapy, Norwich, United Kingdom. 9 Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, Cambridge, United Kingdom. 10 The Clatterbridge Cancer Centre NHS Foundation Trust, Department of