ESTRO 2025 - Abstract Book

S4084

RTT - Patient care, preparation, immobilisation and IGRT verification protocols

ESTRO 2025

Conclusion: Despite a relatively long treatment time, the intrafractional patient movement during OART for rectal cancer is minimal, requiring a CTV-PTV margin of 1.1-1.2 mm. Further research is ongoing to quantify the intrafractional target movement.

Keywords: online adaptive, intrafractional patient movement

References: 1. Brand, V. J., Milder, M. T., Christianen, M. E., Hoogeman, M. S., & Incrocci, L. (2022). Seminal vesicle inter- and intra-fraction motion during radiotherapy for prostate cancer: A review. Radiotherapy and Oncology, 169, 15-24. https://doi.org/10.1016/j.radonc.2022.02.002 2. Van Herk, M. (2004). Errors and margins in radiotherapy. Seminars in Radiation Oncology, 14(1) , 52–64. https://doi.org/10.1053/j.semradonc.2003.10.003 3. De Boer, H. C., & Heijmen, B. J. (2001). A protocol for the reduction of systematic patient setup errors with minimal portal imaging workload. International Journal of Radiation Oncology*Biology*Physics, 50(5) , 1350–1365. https://doi.org/10.1016/s0360-3016(01)01624-8

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Digital Poster Clinical tolerance and practical feasibility of breast cancer radiotherapy planning with continuous positive airway pressure: A real world data report Zeineb Naimi 1 , Amal Riahi 1 , Azza Slim 2 , Raouia Ben Amor 1 , Awatef Hamdoun 1 , Ghada Bouguerra 1 , Rihab Haddad 1 , Roua Toumi 1 , Lotfi Kochbati 1 1 Radiation Oncology Department, Abderrahmen Mami Hospital, Ariana, Tunisia. 2 Pneumology Department, Abderrahmen Mami Hospital, Ariana, Tunisia Purpose/Objective: The aim of this study was to evaluate the practicability of breast cancer radiotherapy planning with continuous positive airway pressure (CPAP) with regards to patient’s tolerance and experience of CPAP breathing.

Material/Methods: We prospectively studied 50 consecutive left-sided breast cancer patients who underwent a planning CT with CPAP.