S861
Clinical - Mixed sites & palliation
ESTRO 2026
Julian P. Layer 1,2 , Cas S. Dejonckheere 1 , Anna-Laura Potthoff 3 , Motaz Hamed 3 , Davide Scafa 1 , Thomas Zeyen 4 , Lea L. Friker 5,2 , Fabian Kugel 1 , Stephan Garbe 1 , Hartmut Vatter 3 , Frank A. Giordano 6,7 , Ulrich Herrlinger 4 , Eleni Gkika 1 , Gustavo R. Sarria 1 , Matthias Schneider 3 1 Department of Radiation Oncology, University Hospital Bonn, Bonn, Germany. 2 Institute of Experimental Oncology, University Hospital Bonn, Bonn, Germany. 3 Department of Neurosurgery, University Hospital Bonn, Bonn, Germany. 4 Department of Neurooncology, Center for Neurology, University Hospital Bonn, Bonn, Germany. 5 Institute of Neuropathology, University Hospital Bonn, Bonn, Germany. 6 Department of Radiation Oncology, University Medical Center Mannheim, University of Heidelberg, Mannheim, Germany. 7 DKFZ-Hector Cancer Institute at the University Medical Center Mannheim, German Cancer Research Center, Mannheim, Germany Purpose/Objective: Intraoperative radiotherapy (IORT) with low-energy X- rays is emerging as a promising alternative to postoperative stereotactic radiotherapy (SRT) for patients with resectable brain metastases (BMs). Potential advantages include immediate dose delivery and expedited initiation or continuation of systemic treatment. Material/Methods: We performed a systematic review of the MEDLINE, Embase, and Scopus databases, including all original articles on IORT for resectable BMs from 2015 − 2025. Data on safety, local control, and survival outcomes were extracted. Additionally, an updated analysis of our institutional IORT cohort was performed for the same endpoints. Results: Ten records (six prospective single-arm trials) encompassing 261 patients were identified. Lung cancer was the most common primary (49%), and 77% of patients presented with a solitary BM. The median prescribed dose was 22.3 Gy (range, 20–30 Gy) using a median applicator size of 2.0 cm. At a median follow- up of 14 (0–79) months, pooled 1-year local control rate (1y-LCR) was 93%, distant brain control 48%, and median overall survival 19 months. Leptomeningeal disease occurred in 6%, and the overall incidence of radiation necrosis was 2.6% (56% grade 1). The median time to next treatment beyond BM therapy was 31 (1- 136) days, significantly shorter than in SRT control collectives. In our center, 132 patients with BM undergoing IORT were identified. In our institutional cohort (n=132), the 1y-LCR was 95.4% with a 1.5% rate of radiation necrosis, corroborating the multicenter
data. Follow-up is ongoing. Conclusion:
IORT for patients with BMs has a favorable toxicity profile and yields excellent local control. Its ability to complete interdisciplinary BM management intraoperatively may facilitate rapid transition to subsequent systemic therapy. An international registry and a prospective randomized phase 3 trial are underway to define the role of IORT among established radiotherapy modalities in the context of resectable BMs. Keywords: Brain metastases, IORT, adjuvant treatment
Digital Poster 480 Stereotactic Body Radiation Therapy in the Management of Bone Metastases from Different Primary Sites María Verónica Vera Merino, Daniela Mariel Angel Schutte, Deborah Middendorf, Maria Jose Almada, Daniel Venencia, Mario Borra, Silvia Zunino Radiation Oncology, Instituto Zunino, Cordoba, Argentina Purpose/Objective: Bone metastasis is common in breast and prostate cancers, and it is associated with intense pain and a high risk of fractures. Its treatment includes various strategies, with stereotactic body radiotherapy (SBRT) standing out as a key option.To evaluate the effectiveness of SBRT in pain control and the incidence of fractures associated with irradiation, as well as to identify the factors linked to clinical response to pain treatment. Material/Methods: Patients treated with SBRT between 2014 and 2021 were included. The metastases were irradiated using SBRT techniques, administering 36 Gy to the GTV and 27 Gy to the CTV in 3 fractions. Statistical analyses were performed using Statistica software version 14.0.0.1, and a significance level of p ≤ 0.05 was considered. Results: A total of 97 patients with 214 metastatic lesions were included in the analysis. Of these, 42 lesions (19.6%) were asymptomatic, while 172 lesions (80.4%) presented with pain at diagnosis. Among the painful lesions, 129 (60.3%) responded to SBRT, with pain reduction greater than 50% observed in 75.2% of
Made with FlippingBook - Share PDF online