KEY POINTS
- This single-institution retrospective analysis included 299 resected brain metastases from 260 patients treated with preoperative stereotactic radiotherapy between 2016 and 2023.
- Single-fraction stereotactic radiosurgery was delivered to 64 lesions as 20 Gy in 1 fraction; fractionated stereotactic radiotherapy was delivered to 235 lesions as 24 Gy in 3 fractions or 25 Gy in 5 fractions.
- The composite endpoint of local failure, nodular meningeal disease, or grade 2 or higher radiation necrosis occurred in 11% of single-fraction lesions and 12% of fractionated lesions; adjusted hazard ratio 0.65 (95% confidence interval 0.25–1.71).
- Local failure occurred in 6.3% versus 2.6% of lesions, while grade 2 or higher radiation necrosis occurred in 6.3% versus 8.9% with single-fraction and fractionated treatment, respectively.
- Leptomeningeal disease occurred in 4.7% of lesions in both groups. Fractionated treatment was used for substantially larger tumors, with median gross tumor volumes of 10 versus 4 cm³.
CLINICAL TAKEAWAY
Both preoperative single-fraction stereotactic radiosurgery and fractionated stereotactic radiotherapy appear reasonable options for resectable brain metastases, with low observed rates of local failure, symptomatic radiation necrosis, and meningeal disease. The study does not establish equivalence or superiority because treatment selection was non-randomized, tumors were larger in the fractionated group, follow-up was limited, and event numbers were low.