OBJECTIVEStereotactic radiosurgery (SRS) is increasingly used for the treatment of brain metastasis. To date, most studies have focused on survival, radiological response, or surrogate quality endpoints such as Karnofsky Performance Scale status or neurocognitive indices. The current study prospectively evaluated pre-procedural factors impacting quality of life in brain metastasis patients undergoing SRS.METHODSUsing a national, cloud-based platform, patients undergoing SRS for brain metastasis were accrued to the registry. Quality of life prior to SRS was assessed using the 5-level EQ-5D (EQ5D-L) validated tool; additionally, patient and treatment attributes were collected. Patient quality of life was assessed as part of routine follow-up after SRS. Factors predicting a difference in the aggregate EQ5D-L score or the subscores were evaluated. Pre-SRS covariates impacting changes in EQ5D-L were statistically evaluated. Statistical analyses were conducted using multivariate linear regression models.RESULTSEQ5D-L results were available for 116 patients. EQ5D-L improvement (average of 0.387) was noted in patients treated with earlier SRS (p = 0.000175). Worsening overall EQ5D-L (average of 0.052 per lesion) was associated with an increased number of brain metastases at the time of initial presentation (p = 0.0399). Male sex predicted a risk of worsening (average of 0.347) of the pain and discomfort subscore at last follow-up (p = 0.004205). Baseline subscores of pain/discomfort were not correlated with pain/discomfort subscores at follow-up (p = 0.604), whereas baseline subscores of anxiety/depression were strongly positively correlated with the anxiety/depression follow-up subscores (p = 0.0039).CONCLUSIONSAfter SRS, quality of life was likely to improve in patients treated early with SRS and worsen in those with a greater number of brain metastases. Sex differences appear to exist regarding pain and discomfort worsening after SRS. Those with high levels of anxiety and depression at SRS may benefit from medical treatment as this particular quality of life factor generally remains unchanged after SRS.