Brain metastases treated with radiosurgery or hypofractionated stereotactic radiotherapy: outcomes and predictors of survival

Introduction To assess treatment outcome and prognostic factors associated with prolonged survival in patients with brain metastases (BM) treated with stereotactic radiosurgery (SRS) or hypofractionated stereotactic radiotherapy (HFSRT). Methods/Patients This study retrospectively reviewed 200 patients with 324 BM treated with one fraction (15-21 Gy) or 5-10 fractions (25-40 Gy) between January 2010 and August 2016. 26.5% of patients received whole brain radiotherapy (WBRT) and 25% initial surgery. Demographics, prognostic scales, systemic and local controls, patterns of relapse and rescue, toxicity, and cause of death were analyzed. A stratified analysis by primary tumor was done. Results Median overall survival (OS) was 8 months from SRS/HFSRT. Breast cancer patients had a median OS of 17 months, followed by renal (11 months), lung (8 months), colorectal (5 months), and melanoma (4 months). The univariate analysis showed improved OS in females (p 0.004), RPA I-II (p < 0.001) initial surgery (p < 0.001), absence of extracranial disease (p 0.023), and good disease control (p 0.002). There were no differences in OS or local control between SRS and HFSRT or in patients receiving WBRT. Among 44% of brain recurrences, 11% were in field. 174 patients died, 10% from confirmed intracranial progression. Conclusions SRS and HSFRT are equally effective and safe for the treatment of BM, with no exceptions among different primary tumors. Disease control, surgery, age, and prognostic scales correlated with OS. However, the lack of survival benefit regarding WBRT might become logical evidence for its omission in a subset of patients.