Commissioning of a 10 MV Photon Beam from an Elekta Synergy Agility Linear Accelerator in the Eclipse Treatment Planning System: A Dosimetric Comparison of AAA and Acuros XB

Published end-to-end validation data for 10 MV photon beams in mixed-vendor radiotherapy environments remain limited. A 10 MV photon beam from an Elekta Synergy Agility linear accelerator was commissioned in Eclipse (version 17.1), and the dosimetric performance of AAA and Acuros XB was evaluated using end-to-end testing. Beam data were measured in a PTW Beamscan water phantom and then imported into Eclipse to generate beam models for AAA and AXB. Eclipse was integrated with the Mosaiq oncology information system to enable better workflow. Following IAEA TECDOC-1583 guidelines, end-to-end test plans were created in Eclipse and delivered to a CIRS thorax phantom (model 002LFC) containing soft-tissue, lung, and bone-equivalent inserts. Absolute dose measurements were compared for AAA, AXB dose-to-water (Dw), and AXB dose-to-medium (Dm), with stopping-power corrections applied for lung and bone regions. End-to-end testing demonstrated good overall agreement for both algorithms. AAA showed consistent performance in soft tissue and closer agreement in bone-equivalent regions, while AXB performed better in lung-equivalent regions. Larger deviations were observed for AXB in posterior beam arrangements where the beam passed through bone before reaching the target. The 10 MV photon beam was successfully commissioned and verified for clinical use in the Eclipse system. Both AAA and AXB demonstrated clinically acceptable accuracy for 3DCRT. Although algorithm-dependent differences were observed in heterogeneous conditions, AAA remains suitable for 3DCRT planning when AXB is unavailable. This work contributes new end-to-end validation data for a 10 MV Elekta-Eclipse configuration, addressing a current gap in the literature for mixed-vendor radiotherapy systems.