ESTRO 2023 - Abstract Book

S2028

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ESTRO 2023

Results 19 patients comprising 65 fractions were analysed. The median number of SRS fractions per patient was 3 [range 3-5]. The most common dose fractionation was 27Gy in 3 fractions using HyperArcTM plans with 3-4 non-coplanar arcs on a Varian Edge Linear Accelerator. The mean residual error was 0.02mm (SD:0.02) (range -0.03 - 0.07) in anterior-posterior direction, 0.02mm (SD:0.04) (range:-0.07 - 0.09) in superior-inferior direction and 0.02mm (SD:0.03) (range:-0.11-0.07) in left-right direction. The mean pitch, roll and rotation residual errors were 0.24° (SD: 0.36) (range -0.6 -1.4), 0.20° (SD: 0.24) (range -0.3-1.1) and 0.21° (SD:0.27) (range -0.4 – 1.2) respectively. The margin compensation for IFM was less than 1 mm for the QFix EncompassTM immobilisation device. Conclusion Sub-millimetre accuracy was confirmed for the QFix EncompassTM immobilisation device during Stereotactic Radiosurgery using HyperArcTM. Post-treatment CBCT is now being eliminated after fraction one during multifraction HyperArcTM SRS treatment deliveries. A detailed analysis of the data to identify trends in patient demographics (ECOG, BMI, Age, Sex, Number of Lesions) and treatment related factors such as treatment time is warranted. J.P. Layer 1 , K. Layer 1 , A. Glasmacher 1 , G. Sarria 1 , A. Böhner 1 , Y.L. Layer 1 , P. Feyer 2 , B. Baumert 3 , R. Baumann 4 , D. Krug 5 , F. Giordano 6 , L.C. Schmeel 1 1 University Hospital Bonn, Department of Radiation Oncology, Bonn, Germany; 2 Vivantes Hospital Neukölln, Institute of Radiation Oncology, Berlin, Germany; 3 Cantonal Hospital Graubünden, Institute of Radiation Oncology, Chur, Switzerland; 4 St. Marien Hospital, Department of Radiation Oncology, Siegen, Germany; 5 University Medical Center Schleswig-Holstein, Department of Radiation Oncology, Kiel, Germany; 6 University Hospital Mannheim, Department of Radiation Oncology, Mannheim, Germany Purpose or Objective Radiation dermatitis (RD) remains the most common side effect in radiation therapy affecting patients’ quality of life and possibly threatening treatment continuation. Various pharmaceutical options are available for both RD prevention and treatment, however no uniform guidelines exist. We sought to determine pharmaceutical management patterns of RD among the German-speaking radiation oncology community. Materials and Methods We conducted a survey on RD among radiation oncology departments and private centers in Germany, Austria and Switzerland inquiring for their opinion on preventive and therapeutic pharmaceutical approaches for acute RD. Results 244 health professionals from academic, non-academic and private centers participated. There was no consensus on the prophylaxis of RD. Several approaches reported by respondents are not recommended in guidelines or sufficiently supported by evidence. Dexpanthenol proved to be the agent most widely used both for prevention (53%) and treatment (76.9%) of RD, followed by urea (29.8%) for RD prevention and corticosteroids (46.9%) for RD treatment. 32.5% of participants did generally not recommend preventative treatment. 53.4% of participants recommend alternative medicine options for RD management. While seldomly used, corticosteroids were considered most effective in RD therapy, followed by dexpanthenol and low-level laser therapy. A majority of participants prefers moist treatment over dry treatment of moist desquamation and 43.75% prescribe antiseptics. Conclusion Pharmaceutical prevention and treatment of RD in the German-speaking radiation oncology community remain uneven and many proceedings are not supported by evidence-based medicine. Stronger evidence level and interdisciplinary consensus is required amongst practitioners to improve these care patterns. 1 University College London Hospitals, Radiotherapy/Proton Beam Therapy, London, United Kingdom; 2 University College London Hospitals, Proton Beam Therapy, London, United Kingdom Purpose or Objective The immobilisation shells for paediatric patients having radiotherapy at UCLH are decorated by an artist to make them more ‘child-friendly’. In photons at UCLH, painting these shells is standard practice, using liquid acrylic paints. In the PBT department, verification MRI scans are done weekly for patients with diagnoses whereby anatomical change is expected. To establish a standard practice across protons and photons, the original paints and an alternative were tested to ensure appropriateness. An alternative paint was sourced, (paint pens from POSCA™). To ensure these were appropriate for PBT and MRI, they were analysed by radiographers and PBT physics, ensuring the outcome was still suitable for purpose (evaluated by PBT play specialists). The original standard paints were evaluated versus POSCA™ paint pens. PO-2255 Pharmaceutical prevention and management of radiation dermatitis in clinical practice PO-2256 An evaluation of the suitability of decorated immobilisation in MRI and Proton Beam Therapy J. O'Brien 1 , C. Gillies 2 , C. Hardy 1

Two evaluations were done to establish:

• The effect of the paint used on MR imaging