ESTRO 2025 - Abstract Book

S1576

Clinical – Mixed sites & palliation

ESTRO 2025

Keywords: Oligometastasis, Thymic tumors, Oligoprogression

References: 1. Guckenberger M, Lievens Y, Bouma AB, et al. Characterisation and classification of oligometastatic disease: a European Society for Radiotherapy and Oncology and European Organisation for Research and Treatment of Cancer consensus recommendation. Lancet Oncol . 2020;21(1):e18-e28. doi:10.1016/S1470-2045(19)30718-1

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Digital Poster Survival and Progression Outcomes in Vertebral Metastases: A Comparative Analysis of SBRT and EBRT Mateo Jukic, Leonie von Brunn, Marco ME Vogel, Kerstin A Eitz, Stephanie E Combs Radiation Oncology, Klinikum rechts der Isar, TUM, Munich, Germany Purpose/Objective: Vertebral metastases (VM) are a common indication for radiotherapy.[1] Since treatment regimens using conventional external beam radiotherapy (EBRT) show only moderate efficacy[2][3], stereotactic body radiotherapy (SBRT) is gaining importance for its potential to deliver higher and more precise doses[4]. However, there is a lack of evidence-based data comparing these two radiotherapy modalities. This study aims to compare EBRT and SBRT in terms of local control, oncologic outcome, and overall survival of patients. Material/Methods: A monocentric, retrospective data analysis of approximately 1,150 patients with VM treated with radiotherapy (RT) between 2001 and 2021 is being conducted. Collected data include time of diagnosis, administered treatments, disease progression, and time of death. The median follow-up period after RT was 8.7 months (IQR 2.5 – 27.7 months). Results: To date, 843 patients (556 male, 287 female) who received a total of 1215 RTs have been included in the analysis, comprising 1118 EBRTs and 97 SBRTs. The median age of patients is 67 years (IQR 57 – 74). The three most common tumor types in this cohort are carcinomas of the prostate, breast, and lung. Local control was achieved for an average of 52.25 ± 3.6 months. Among patients who received SBRT, local progression occurred after a mean of 76.4± 7.7 months, compared to 48.7± 3.73 months for those treated with EBRT. Systemic progression occurred a median of 13.7 months (95% CI 11.0 – 16.0) following RT. For patients treated with SBRT, systemic progression occurred at a median of 16.6 months (95% CI 11.9 – 27.0) after RT, compared to a median of 13.7 months (95% CI 11.8 – 15.4) in those treated with EBRT. The median overall survival following vertebral RT was 16.3 months (95% CI 13.2 – 20.1). Patients treated with SBRT had a median survival of 85.2 months (95% CI 38.6 – NA), compared to a median of 13.3 months (95% CI 11.4 – 16.6) for those treated with EBRT. Conclusion: SBRT is an increasingly utilized modality for treating VM. This study suggests a potential superiority of SBRT over EBRT in terms of local control. Further analyses of this heterogeneous patient cohort are needed to identify influencing factors.

Keywords: SBRT, vetrebral metastasis,

References: [1] R. E. Coleman, Clinical Cancer Research 2006, 12, 6243s [2] M. Huisman, M. A. van den Bosch, J. W. Wijlemans, M. van Vulpen, Y. M. van der Linden, H. M. Verkooijen, Int J Radiat Oncol Biol Phys 2012, 84, 8-14.