In a study reported in JAMA Oncology, Prabhu et al identified outcomes and associated risk factors among patients receiving stereotactic radiosurgery (SRS) prior to resection of brain metastases from solid tumors.
Study Details
The study involved data from an international multicenter cohort (Preoperative Radiosurgery for Brain Metastases–PROPS-BM). The current study cohort included 404 patients from eight sites in the United States and Australia who were treated between 2005 and 2021, with most being treated since 2017.
Patients received SRS to at least one lesion prior to surgery; SRS to synchronous intact metastases was permitted. SRS was given at a median dose of 15 Gy in 1 fraction or 24 Gy in 3 fractions, delivered at a median of 2 days (interquartile range = 1–4 days) before resection.
Key Findings
The 2-year cavity local recurrence rate was 13.7% (95% confidence interval [CI] = 10.3%–17.6%). Reduced risk was associated with active vs nonactive systemic disease (hazard ratio [HR] = 0.33, P < .001), gross total vs subtotal resection (HR = 0.2, P = .001), fractionated vs single-fraction SRS (HR = 0.15, P = .01), and en bloc vs piecemeal tumor resection (HR = 0.34, P = .03). A trend toward increased risk was observed for gastrointestinal vs non–small cell lung cancer (NSCLC) primary tumors (HR = 3.0, P = .06).
The 2-year rate of meningeal disease was 5.8% (95% CI = 3.5%–8.8%). Factors associated with risk were gross total vs subtotal resection (HR = 0.18, P = .003) and breast primary (HR = 5.64, P = .01), melanoma primary (HR = 7.9, P = .003), and other primary cancer type (HR = 4.6, P = .03) vs NSCLC. A trend was observed for posterior fossa vs supratentorial location (HR = 2.4, P = .06).
The 2-year rate of any-grade adverse radiation effects was 7.4% (95% CI = 5.0%–10.5%). Factors associated with risk of adverse radiation effects were planning target volume (PTV) expansion > 1 vs ≤ 1 mm (HR = 2.93, P = .01) and melanoma primary vs NSCLC (HR = 2.59, P = .04). The 2-year any-grade adverse radiation effect rates for PTV margin expansion of ≤ 1 mm vs > 1 mm were 5.8% vs 20.5% (P = .004).
Median overall survival was 17.2 months (95% CI = 14.1–21.3 months), with a 2-year rate of 41.7% (95% CI = 36.3%–46.9%). Factors associated with risk of death were active vs nonactive systemic disease (HR = 1.56, P = .003), increasing age (HR = 1.02, P = .001), gross total vs subtotal resection (HR = 0.35, P < .001), and melanoma primary (HR = 0.55, P = .01) and kidney primary (HR = 0.57, P = .03) vs NSCLC.
The investigators concluded, “In this cohort study, the rates of cavity local recurrence, adverse radiation effects, and meningeal disease after preoperative SRS were found to be notably low. Several tumor and treatment factors were identified that are associated with risk of cavity local recurrence, adverse radiation effects, meningeal disease, and overall survival after treatment with preoperative SRS. A phase III randomized clinical trial of preoperative vs postoperative SRS (NRG BN012) has began enrolling ([ClinicalTrials.gov identifier] NCT05438212).”
Roshan S. Prabhu, MD, MS, of Levine Cancer Institute, Atrium Health, Charlotte, North Carolina, is the corresponding author for the JAMA Oncology article.
Disclosure: For full disclosures of the study authors, visit jamanetwork.com.
