Occurrence of Seizures Prior to Single-fraction Radiosurgery or Multi-fraction Stereotactic Radiotherapy in Patients With Very Few Brain Metastases

Background/aim: Seizures represent a major problem for patients with brain metastases. This study evaluated the role of seizures in patients receiving single-fraction radiosurgery (SRS) or multi-fraction stereotactic radiotherapy (FSRT).

Patients and methods: This retrospective study included 195 patients receiving SRS (n=164) or FSRT (n=31) alone for one to three brain metastases. The prevalence of pre-SRS/FSRT seizures and correlations with pre-treatment factors were investigated. These factors plus pre-SRS/FSRT seizures were assessed in regard to survival.

Results: Thirty-three patients had pre-SRS/FSRT seizures (prevalence=16.9%). Seizures were significantly correlated with age ≤61 years. Trends were observed for seizures being more frequent in those with NSCLC and those without extra-cranial metastatic spread. On multivariate analysis, significant associations with improved survival were found for Karnofsky performance score ≥80%, breast cancer, and an interval from diagnosis of malignant disease to SRS/FSRT ≥21 months.

Conclusion: Younger age, NSCLC and absence of extra-cranial spread appeared to be risk factors for seizures prior to SRS/FSRT. Having seizures prior to SRS/FSRT showed no association with survival.

Keywords: Brain metastases; radiosurgery; seizures; stereotactic radiotherapy.