ESTRO 2025 - Abstract Book

S1558

Clinical – Mixed sites & palliation

ESTRO 2025

The median EQD2 (assuming an α/β=10) was 42.75 Gy (range 30– 96 Gy). The actuarial LC rates were 95% and 89% at 1 and 3 years, respectively. No significant associations were found between LC and factors such as age, primary histology, lesion location, EQD2 (>40 Gy), or treatment technique. Among the 37 patients who presented pain at baseline, the actuarial pain control rate was 79% at 6 months and 60% at 12 months (median 20 months). Patients receiving an EQD2 > 40 Gy had statistically longer median PC (NR vs 8 months, p=0.04). No other clinical or dosimetric factors were found to affect PC (Figure 1). Interestingly, only one patient had a non-symptomatic rib fracture and three patients experienced pain flare.

Conclusion: Our trial confirms that SBRT for rib metastases offers high local control and sustained pain relief. Moreover, these results suggest that high-dose regimens may enhance pain management and prevent symptom progression with minimal toxicity.

Keywords: Pain control, rib

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