Serum levels of S-100B protein (S-100B) and neuron-specific enolase (NSE) are elevated after various cerebral injuries and are considered markers of central nervous system damage. In brain tumor patients, literature data on the prognostic value of serum S-100(B) and NSE levels are scarse and conflicting. We assessed serum S-100B and NSE levels in 20 consecutive cerebral glioma patients, and evaluated serum levels in relation to survival to determine their prognostic value. Kaplan-Meier survival curves were constructed for patients with "high" (> median value) versus "low" (< or = median value) serum S-100B and NSE levels. A statistically significant shorter survival was found in patients with high serum S-100B levels, whereas a similar classification of patients based on serum NSE levels demonstrated no statistically significant difference in survival between the two groups. These preliminary data suggest that serum S-100B might be a prognostic variable in cerebral glioma patients. Further study is warranted to evaluate whether serum S-100B is an additional, independent prognostic variable.