Background/Aim: Seizures can be the initial symptom of brain metastases. This study investigated pretreatment seizures in patients with a single lesion. Patients and Methods: Pre-operative seizures were analyzed in 104 patients with a single brain metastasis receiving resection plus whole-brain irradiation and a boost. Prevalence of seizures, risk factors and associations with survival (OS) were evaluated. Results: Thirty patients (34.6%) had seizures prior to neurosurgery. Significant associations between seizures and investigated characteristics were not found. However, age ≤61 years showed a trend (p=0.117) for increased incidence of seizures. Time from diagnosis of malignancy until neurosurgery >12 months was significantly associated with improved OS on univariate analysis (p=0.003). Trends for a positive association with OS were found for no seizures (p=0.054), female gender (p=0.066) and breast cancer (p=0.098). On multivariate analysis, time until neurosurgery >12 months was independently associated (p=0.019) with better OS, and seizures showed a trend (p=0.119) for improved OS. Conclusions: Considering the high prevalence of seizures in this cohort, regular screening and monitoring of these patients appears reasonable. This applies particularly to patients aged ≤61 years. Metastasis to the brain represents a relatively common situation in adult cancer patients and is often associated with serious symptoms impairing quality of life (1, 2). With respect to the number of lesions, patients can be classified as having single brain metastasis, oligo-metastatic disease (usually up to three lesions) or multiple brain metastases (usually more than three lesions) (2). A serious problem in patients with brain metastasis is the occurrence of seizures (3). Seizures can occur prior to the start of treatment and even be the initial symptom leading to the diagnosis of brain metastasis. Pre-treatment seizures appear much more common than seizures occurring during treatment or follow-up (3). Moreover, occurrence of seizures may be associated with the number of intracerebral lesions. However, the data reported appear conflicting. In the study of Wu et al., pre-operative seizures were significantly associated with more than two intracerebral lesions, whereas in the study of Wolpert et al., no significant association between pre-operative seizures and the number of brain metastases was observed (4, 5). Nevertheless, in the study of Wolpert et al., single brain metastasis was the most important risk factor for seizures in non-operated patients (5). It appears reasonable to perform separate studies in patients with single, limited numbers or multiple intracerebral lesions, as well as in patients treated with or without neurosurgical resection to properly define the role of seizures in patients with brain metastasis. This study focused on patients with a single intracerebral lesion who received resection of their metastasis followed by whole-brain irradiation (WBI) and a boost to the resection cavity. Patients and Methods Patien...