S1968
Physics - Dose prediction/calculation, optimisation and applications for photon and electron planning
ESTRO 2026
included D98% > 95%, D99% > 95%, D107% < 1.8 cc, and DAHANCA 2020 dose limits for OARs. - Prostate + LNs (72 Gy / 28 fractions): included 7 target structures and 7 OARs, with a maximum score of 152 points. Metrics included V107% < 4%, D98% > 95%, and clinical OAR constraints for rectum, bladder, bowel, and femoral heads. Two RapidPlan knowledge-based planning models (H&N and Prostate + LNs) were trained on 100 and 126 approved clinical plans, respectively. Twenty patients per site were evaluated, and plan scores were compared between manual and RapidPlan-generated plans. Results: For prostate + LNs, mean scores were 107.1 points (70.2%) and 110.6 points (72.6%) for manual and RapidPlan plans, respectively (Fig. 1).For H&N plans, mean total scores were 138.0 points (63%) for manual plans and 136.8 points (62.5%) for RapidPlan (Fig. 2).Most results were within ±10% of the mean, allowing definition of clinical quality thresholds:– H&N: acceptable ≥ 56%, good ≥ 62%, very good ≥ 69%.– Prostate: acceptable ≥ 65%, good ≥ 73%, very good ≥ 80%.Figure 1.Prostate + LNs 72 Gy — Scorecard %: Manual vs RapidPlan (shaded area = ±10% band of site baseline).
and reduced OAR high-dose migration. On recalculation, VHEE’s only degradation was a hotspot constraint breach with coverage preserved; VMAT more often combined coverage loss with OAR overdose. These anatomically based findings extend the commonly cited heterogeneity insensitivity of VHEE beyond simple geometries and motivate validation in larger cohorts with deformable dose accumulation to generalise across sites. References: [1] Yan D., et al. Adaptive radiation therapy. Phys Med Biol, 1997. doi:10.1088/0031-9155/42/1/008.[2] DesRosiers C., et al. 150–250 MeV electron beams in radiation therapy. Phys Med Biol, 2000. doi:10.1088/0031-9155/45/7/306.[3] Lagzda A., et al. Influence of heterogeneous media on Very High Energy Electron (VHEE) dose penetration and a Monte Carlo-based comparison with existing radiotherapy modalities. Nucl Instrum Methods B, 2020. doi:10.1016/j.nimb.2020.09.008.[4] D’Andrea F. S., et al. Comparative treatment planning of very high- energy electrons and photon volumetric modulated arc therapy: Optimising energy and beam parameters.
Phys Imaging Radiat Oncol, 2025. doi:10.1016/j.phro.2025.100732. Keywords: VHEE, VMAT, Anatomical Change
Digital Poster 3960 Quality Plan Assessment using Scorecard for H&N and Prostate Manual Plans vs. RapidPlans Jan Konieczek 1 , Joanna Kami ń ska 2,3 1 Departmet of Oncology and Radiotherapy, University Clinical Centre, Gda ń sk, Poland. 2 Department of Oncology and Radiotherapy, Medical University, Gda ń sk, Poland. 3 Department of Oncology and Radiotherapy, University Clinical Centre, Gda ń sk, Poland Purpose/Objective: The quality of radiotherapy plans depends on achieving optimal target coverage while minimizing the dose to organs at risk (OARs). Dosimetric scorecards provide an objective and quantitative way to evaluate plan quality using predefined dose–volume metrics, thereby reducing inter-planner variability. This study aimed to evaluate and compare the quality of manually created and knowledge-based (RapidPlan) radiotherapy plans for head and neck (H&N) and prostate cancer using the MAAS Scorecard tool (Varian
Figure 2. H&N 66 Gy — Scorecard %: Manual vs RapidPlan (shaded area = ±10% band of site baseline).
Inc., Palo Alto, USA). Material/Methods:
Two scorecard templates were implemented in Eclipse/ARIA 18.0.1: - H&N (66 Gy / 33 fractions): included 4 target structures and 17 OARs, with a maximum score of 219 points. Evaluation metrics
Made with FlippingBook - Share PDF online