ESTRO 2025 - Abstract Book

S4045

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

ESTRO 2025

results provide strong evidence that the vacuum mattress improves treatment consistency, potentially enhancing the dose-effect relationship of HT and RT.

Keywords: Superficial hyperthermia positioning

References: 1. Niloy R Datta, Emsad Puric, Dirk Klingbiel, Silvia Gomez, Stephan Bodis. Hyperthermia and Radiation Therapy in Locoregional Recurrent Breast Cancers: A Systematic Review and Meta-analysis. Int J Radiat Oncol Biol Phys. 2016 Apr 1;94(5):1073-87. doi: 10.1016/j.ijrobp.2015.12.361. Epub 2015 Dec 21. 2. Bakker A., Van Der Zee J., Van Tienhoven G., Kok H.P., Rasch C.R.N., Crezee H. Temperature and thermal dose during radiotherapy and hyperthermia for recurrent breast cancer are related to clinical outcome and thermal toxicity: A systematic review. Int. J. Hyperth. 2019;36:1023–1038.

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Digital Poster Analyze the positioning error of spinal metastasis and the influence and the importance of six-degree couch on spinal metastasis wenhua qin 1 , tao zhang 1 , xin feng 1 , zengzhou wang 1 , hong wang 1 , shiyu wu 1 , cheng chen 1 , fukui huan 1 , shangnan chu 2 1 Department of radiation oncology, Cancer Hospital Chinese Academy of Medical Science, beijing, China. 2 Department of radiation oncology, Peking University Cancer Hospital, beijing, China Purpose/Objective: To Investigate the setup errors of cervical spine,thoracic spine,and lumbar spine under the guidance of cone beam CT in three-degree couch and six-degree couch and to analyze the errors of vertebral body in six-degree of freedom and the necessity and significance of six-degree couch in correcting the translation and rotation direction of patients with spinal metastasis. Material/Methods: One hundred and twenty-five cases of patients with spinal metastasis were treated using radiotherapy were selected.They were divided into control group(using three-degree couch and calibration) and experimental group(using six-degree couch and calibration).Among them,69 cases in the control group were 9 cases of cervical spine,33 cases of thoracic spine and 27 cases of lumbar spine.In the experimental group,56 cases were 10 cases of cervical spine,21 cases of thoracic spine and 25 cases of lumbar spine.A total of 946 CBCT data were collected in this study,including 171 in cervical spine,407 in thoracic spine and 368 in lumbar spine.Translational shifts in 3 axes (AP: anterior posterior; LR: left right; and SI: superior inferior)after CBCT were analyzed.The random and systematic setup errors(SE) were calculated.

Results: