ESTRO 2025 - Abstract Book

S1495

Clinical – Mixed sites & palliation

ESTRO 2025

Conclusion: This study provides the first evidence-based assessment of the 0-7-21 palliative radiotherapy regimen for breast tumors, offering new insights into its potential role in clinical practice. While the 0-7-21 regimen demonstrated clinically meaningful trends toward improved symptom control and radiological mass reduction compared to 20 Gy in 5 fractions, the differences were not statistically significant likely due to the small sample size. Larger, prospective studies are needed to validate these findings and refine the role of the 0-7-21 regimen in palliative radiotherapy in breast cancer.

Keywords: Breast Cancer, Palliative Radiotherapy

References: 1. Cox JD, Stetz J, Pajak TF. Toxicity criteria of the Radiation Therapy Oncology Group (RTOG) and the European Organization for Research and Treatment of Cancer (EORTC). Int J Radiat Oncol Biol Phys. 1995 Mar 30;31(5):1341-6. doi: 10.1016/0360-3016(95)00060-C. PMID: 7713792.

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Digital Poster LOW-DOSE RADIOTHERAPY FOR PAINFUL MUSCULOSKELETAL DISORDERS: 10 YEARS FOLLOW-UP. Beatriz Álvarez, Ángel Montero, Jeannette Josefina Valero, Rosa María Alonso, Ovidio Hernando, Raquel Ciérvide,

Emilio Sánchez, Mercedes López, Mariola García-Aranda, Carmen Rubio Radiation Oncology, Hospital Universitario HM Sanchinarro, Madrid, Spain

Purpose/Objective: Evaluation of long-term response of painful musculoskeletal disorders (PMD) after low-dose radiotherapy (LDRT).

Material/Methods: Patients enrolled in this prospective analysis underwent CT-based simulation using different immobilisation devices depending on location to be treated. Planning target volumes, including painful location and peri-articular soft tissues, were defined according to already published atlas. Treatment was delivered in a LINAC and daily verified with orthogonal X-ray or KV-Conebeam-CT. 1 Gy fractions were delivered every other day up to a total dose of 6 Gy. Those patients achieving insufficient response were offered a second course of LDRT 10-12 weeks after finishing first course. Pain was measured before and after radiotherapy, as well as every 3-6 months. Using for this porpuse the visual analogue scale (VAS), the functional von Pannewitz scale and determining variations in analgesics intake. Results: Between April-2015 and June-2024, we treated 260 patients (207 women and 53 men) with a median age of 65 years old (range 30-90 years) presenting with arthritis (68.5%), fasciitis (5.4%), bursitis (22.3%) or synovitis (3.8%).