ESTRO 2024 - Abstract Book

S798

Clinical - CNS

ESTRO 2024

Figure 1. Kaplan-Meier curves for OS (left) and bPFS (right) by histology (top) and by extracranial metastases site (bottom).

No statistically significant differences (P>0.05) in clinical outcomes were found for number of treated lesions, total target volume, BM minimum dose and systemic therapy. Patient age and gender showed borderline significant correlations with bPFS (P=0.055) and ifPFS (P=0.060), respectively. Extended bPFS was observed in younger than 66 years patients (mean, 9.9 vs 6.4 months), while female patients had superior ifPFS (mean, 11.6 vs 9.1 months). At multivariate analysis, lung primary tumor histology was independently related to brain progression (OR, 0.35; 95% CI, 0.12 – 0.98; P=0.043).

Conclusion:

Linac-based SRS/fSRS treatments with single-isocenter coplanar FFF-VMAT technique were feasible and resulted in encouraging LC outcomes, comparable to other treatment approaches involving multiple non-coplanar arcs or dedicated machines. Patient prognosis remains unfavorable, mostly dependent on histology and extracranial disease status, rather than on the radiation treatment. Further analyses on a larger patient population are currently underway to confirm these findings and to investigate additional significant predictive factors.

Keywords: Radiosurgery, Outcomes, Predictive Factors