ESTRO 2024 - Abstract Book

S1707

Clinical - Lung

ESTRO 2024

A higher median BED10 was administered for Group B and C lesions versus Group A lesions (100 Gy and 96 Gy vs 59.5 Gy; p = 0.05). Median estimated follow-up was 16 months (95%CI 11.8-23). One-, 2-, and 3-year LC rates were 95.7% (95%CI 84.0-98.9), 86.2% (95%CI 64.8-95.0), and 78.4% (95%CI 51.3-91.5), respectively. Median OS and PFS were 47.4 months (95%CI 24.2-77.1) and 26.7 months (95%CI 13.3-NE), respectively. Regarding the clinical toxicity after SABR, there were 31 cases (54.4%) of G1-2 adverse events, while no G3 toxicity occurred. One patient (1.8%) died of post-acute pneumonitis with respiratory failure (G5) 15 weeks after SABR. Radiological bronchial damage occurred in 14 (23.3%) cases as lobar, segmental, and sub-segmental stenosis in 2 (3.3%), 9 (15%), and 3 (5%), respectively. One- and 2-year radiological bronchial event free survival were 79.9% (95%CI 68.8-92.7) and 66.2% (95%CI 52.1-84.1), respectively. The actuarial rate for any type of radiological bronchial toxicity is represented in Figure 1. All lobar stenosis occurred for GTV location <1 cm from the trachea/main bronchi (Group A; p = 0.002). No other variables correlated to incidence or type of bronchial toxicity.