S1264
Clinical - Urology
ESTRO 2026
supports the use of both techniques in daily practice. Keywords: prostate, hypofractionated, boost
of Radiation Oncology, University Medical Center Schleswig-Holstein, Kiel, Germany
Purpose/Objective: To evaluate the efficacy and safety of hypofractionated and dose-boosted radiotherapy (RT) fractionation schedules for localized prostate cancer (PCa). We hypothesized that dose-boosting improves clinically relevant endpoints like metastasis-free survival (MFS), that hypofractionation may confer benefits due to increases in equivalent dose in 2Gy fractions (EQD2), and that modern RT techniques allow for safe delivery of hypofractionated regimens. Material/Methods: This prospectively-registered systematic review and meta-analysis followed PRISMA guidelines (PROSPERO: CRD42024601045). We searched MEDLINE, Embase, Web of Science, CENTRAL, and Google Scholar up to June 15, 2025, for randomized controlled trials (RCTs) with EQD2 ≥ 70Gy in both arms. Outcomes included biochemical recurrence-free survival (BRFS), MFS, overall survival (OS), and grade ≥ 2/ ≥ 3 adverse events (AEs; genitourinary [GU] or gastrointestinal [GI], acute or late). Risk of bias was assessed using Cochrane RoB 2. Random-effects meta-analyses were used to pool hazard ratios (HRs) with 95% confidence intervals (CIs). Results were stratified by RT types and EQD2 differences ( ≥ 10% increase threshold). Sensitivity analyses addressed α / β variations, androgen deprivation therapy (ADT), risk groups, and heterogeneity. Risk of bias was assessed using Cochrane RoB 2 tool. Results: Twenty-five RCTs (n=12,479) were included. Studies assessing dose-boosting (n=1,468) showed improved MFS (HR 0.76, 95% CI 0.60-0.96) and BRFS (HR 0.43, 95% CI 0.32-0.58); sensitivity analysis suggested OS benefit with extended follow-up (n=897, HR 0.75, 95% CI 0.60-0.95). Hypofractionation studies (n=10,220) showed minor BRFS improvement (HR 0.88, 95% CI 0.76-1.00), not well-correlated with EQD2 ( α / β =1.5Gy), with no MFS or OS differences. Moderate hypofractionation increased acute G ≥ 2 GI AEs (RR 1.43, 95% CI 1.32-1.56); ultra-hypofractionation increased acute G ≥ 3 GU AEs (RR 1.89, 95% CI 1.16-3.09). No significant differences were identified for late AE. The main limitations include high risk of bias in the dose- boost analysis due to concerns regarding randomisation; heterogeneity in trial designs, study populations, androgen deprivation therapy (ADT) use, and elective pelvic lymph node irradiations; and reliance on aggregate data. Conclusion: Dose-boosting improves survival in high-risk PCa. Hypofractionation reduces treatment time without compromising oncologic outcomes, and is associated with only modest acute toxicity increases. This
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Hypertension is significantly associated with better outcomes in high-risk patients with prostate cancer Niamh Murphy 1,2 , Emma Allott 2 , Declan McKenna 1 , Suneil Jain 2,3 , Ross Murphy 1,2 1 Centre for Genomic Medicine, Ulster University, Coleraine, United Kingdom. 2 Prostate Cancer Centre of Excellence, Queen’s University, Belfast, United Kingdom. 3 Northern Ireland Cancer Centre, Belfast Health and Social Care Trust, Belfast, United Kingdom Purpose/Objective: Prostate cancer is among the most common causes of cancer-related mortality for males globally. A major challenge lies in distinguishing indolent from potentially fatal disease at the time of diagnosis. Hypertension is associated with an increased risk of developing prostate cancer. However, evidence suggests that antihypertensive medication usage could be associated with better outcomes for patients with prostate cancer. Despite this, the underlying tumour biology associated with hypertension in patients with prostate cancer has not been characterised. Material/Methods: We analysed 466 patients with intermediate-to-high risk prostate cancer receiving radiotherapy and androgen deprivation therapy, of whom 248 patients had tumour gene expression profiling. High-risk prostate cancer was defined as Cambridge Prognostic Group (CPG) 4 or 5, or having a Gleason score ≥ 8. Multivariate survival analysis, including age and initial prostate specific antigen levels as covariates, was used to determine the relationship between hypertension status at diagnosis with prostate cancer, prostate cancer risk groups, and metastatic disease. Differential gene expression was performed for hypertension status at diagnosis with prostate cancer and metastatic disease. Immune and stromal cell estimation scores, and Hallmark gene sets, were inferred using patient tumour gene expression profiles and compared by hypertension status. Results: Hypertension status at diagnosis with prostate cancer was not associated with development of metastatic disease. When stratifying by Gleason score risk, hypertension was associated with significantly better outcomes for metastatic disease in high-risk patients (HR = 0.43, p-value = 0.009), but not in low- and intermediate-risk patients (HR = 1.86, p-value = 0.18; p- interaction = 0.022). However, when classifying by CPG
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