ESTRO 2025 - Abstract Book

S461

Clinical - Breast

ESTRO 2025

Among the 5 resubmissions, one inexperienced centre was paired with an experienced centres after two unacceptable benchmark submissions. This centre was approved on third submission. All centres benchmarked ultimately complied with trial protocol. Conclusion: The PARABLE trial RTQA programme has effectively supported centres in developing their photon SIB VMAT technique. Prior SIB VMAT experience did not appear to impact protocol compliance but these numbers were small. For some OARs, experience appeared to influence plan quality. A robust RTQA programme with associated guidance document and centre-focused support has resulted in benchmark protocol-compliant plans, independent of prior experience, allowing centres to develop new techniques safely and effectively through a clinical trial.

Keywords: Breast, simultaneous integrated boost, VMAT

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Digital Poster Long-term cardiac outcomes in breast cancer patients treated with tomotherapy: evaluating the applicability of 3D-based dose constraints for IMRT Pierre Loap, Abdelkarim Uakkas, Jihane Bouziane, Alain Fourquet, Youlia Kirova department of radiation oncology, Institut Curie, Paris, France