Stereotactic radiosurgery in brain metastasis: treatment outcomes and patterns of failure

Introduction:Stereotactic radiosurgery (SRS) has become a preferred treatment in the initial management of brain metastases (BM). This study reported treatment outcomes and identified the patient, tumour, and treatment-related factors that predict failure, survival, and brain necrosis (BN). Methods:We retrospectively reviewed the electronic medical records of all BM patients treated with SRS. Patient, tumour characteristics and treatment details data were collected. All recurrences and BN were defined in the neurooncological tumour board. Results:From December 2016 to April 2020, 148 patients were analysed. The median follow-up was 14 center dot 8 months (range 6-51). At the time of analyses, 72 center dot 3% of the patients were alive. Presence of initial neurological deficit (HR; 2 center dot 71 (1 center dot 07-6 center dot 9); p = 0 center dot 036) and prior RT (HR; 2 center dot 55 (1 center dot 28-5 center dot 09); p = 0 center dot 008) is associated with worse overall survival. The local recurrence rate was 11 center dot 5 %. The distant brain metastasis rate was 53 center dot 4 %. Leptomeningeal metastasis was seen in 11 patients (7 center dot 4%). Symptomatic BN was seen in 19 patients (12 center dot 8 %). Bigger lesions (13 versus 23 mm diameter; p = 0 center dot 034) and cavity radiosurgery are associated with more BN (63 center dot 2 % versus 36 center dot 8%; p: 0 center dot 004). Conclusions:Distant BM is the leading cause of CNS recurrences and, salvage SRS is possible. Due to the increasing risk of developing BN routine metastasectomy should be made with caution.