S1258
Clinical - Urology
ESTRO 2026
Proffered Paper 3329
Philips) and on HyperSight™ CBCTs [2] acquired before the first (FF), second (SF), and last fraction (LF). Proximal pelvic muscles included the tensor fasciae latae (TFL), sartorius, and iliopsoas, while distal levels comprised the TFL, sartorius, and rectus femoris. A gluteal subcutaneous fat region of interest (ROI) was delineated for HU normalization. Muscle cross- sectional area (CSA) and density (HU, z-standardized) were quantified at baseline (BPL) and at the CBCT timepoints (FF, SF, LF). Longitudinal trajectories were analyzed using linear mixed models with post-hoc adjusted contrasts. Results: CSA declined progressively during treatment, with a significant reduction at LF compared to BPL ( Δ = − 238 mm ² , p ₐ d ⱼ = 0.0003); SF showed an intermediate decline ( − 112 mm ² , p = 0.049). Muscle density (zHU) decreased significantly at LF versus FF ( Δ = − 0.62, p ₐ d ⱼ < 0.001). The corresponding longitudinal trajectories (mean ± 90 % CI) are shown in Figure 1A–B. Conclusion: HyperSight™ CBCT enables quantitative skeletal- muscle assessment during prostate RT. Continuous decline in muscle mass and density was detectable throughout treatment, reflecting measurable sarcopenic changes. CBCT-based sarcopenia monitoring is feasible and may serve as a biomarker for adaptive and supportive care strategies during high precision RT. References: 1. Huang, W., et al., Skeletal Muscle Mass Measurement Using Cone-Beam Computed Tomography in Patients With Head and Neck Cancer. Front Oncol, 2022. 12: p. 902966.2. Lustermans, D., et al., Image quality evaluation of a new high- performance ring-gantry cone-beam computed tomography imager. Physics in Medicine & Biology, 2024. 69(10): p. 105018. Keywords: CBCT, Sarcopenia monitoring, Prostate radiotherapy
Patient-Reported Outcomes from a Randomized Non-inferiority Trial of Hypofractionation via Extended vs. Accelerated Therapy (HEAT) for Prostate Cancer David J Lee 1 , Sunwoo Han 2 , Umberto Ricardi 3 , Giuseppe Carlo Iorio 4 , Thomas Eade 5 , Andrew Kneebone 5 , Debra E Freeman 6 , Frank J Penedo 7 , Radka Stoyanova 1 , Nesrin Dogan 1 , Benjamin Oren Spieler 1 , Sanoj Punnen 8 , Alan Dal Pra 1 , Brandon A Mahal 1 , Alan Pollack 1 , Matthew C Abramowitz 1 1 Department of Radiation Oncology, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, USA. 2 Biostatistics and Bioinformatics Shared Resource, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, USA. 3 Department of Oncology and Radiation Oncology, University of Turin, Turin, Italy. 4 Department of Radiation Oncology, University of Turin, Turin, Italy. 5 Department of Radiation Oncology, Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, Australia. 6 Department of Radiation Oncology, Naples Radiation Oncology, Naples, USA. 7 Department of Psychology, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, USA. 8 Department of Urology, Desai Sethi Urology Institute, University of Miami Miller School of Medicine, Miami, USA Purpose/Objective: A strong radiobiological rationale supports hypofractionation in radiotherapy (RT) of prostate cancer (PCa). Stereotactic techniques may extend these benefits to patients and society by reducing costs, improving access, and decreasing patient/caregiver burden, while delivering comparable outcomes in five fractions. HEAT is an international randomized phase III trial that shows comparable four-year biochemical failure and overall genitourinary/gastrointestinal toxicity in a one-to-one comparison of extended (EHRT) and accelerated hypofractionation (AHRT). The analysis of early patient-reported outcomes (PROs) from HEAT are presented herein. Material/Methods: HEAT randomized 142 men aged 35-85 with low- (17.6%) to intermediate-risk (82.4%) localized PCa, of prostate-specific antigen ≤ 20 and International Prostate Symptom Score (IPSS) ≤ 12, to either EHRT to 70.2 Gy in 26 fractions (n=70) or AHRT to 36.25-40 Gy in five fractions (n=72), stratified by risk group, prostate volume, and androgen deprivation therapy (ADT; ≤ 6 months permitted). IPSS, EPIC-SF12, and MAX- PC scores were collected pre-RT (baseline) and at three, nine, and 15 months post-RT. Data were
Made with FlippingBook - Share PDF online