CD34 expression in low-grade epilepsy-associated tumors: relationships with clinicopathological features

OBJECTIVE: To analyze the relationships between CD34 expression and several demographic, clinical and pathological features, in patients with histopathological evidence of low-grade epilepsy-associated tumors (LEATs) who underwent epilepsy surgery.

METHODS: We conducted a retrospective study enrolling 187 patients with LEATs who underwent surgery between January 2009 and June 2015 at eight Italian epilepsy surgery centers. All cases were histologically diagnosed according to the WHO classification of tumors of the central nervous system. Univariate and multivariate analyses were performed to identify variables associated with CD34 expression.

RESULTS: Ninety-five (50.8%) out of 187 patients were CD34 positive. At multivariate analysis, tumor type and duration of epilepsy were independently associated with CD34 expression. Ganglioglioma and pleomorphic xanthoastrocytoma were the histotypes with the strongest association with CD34 positivity, with an odds ratio (OR) of 9.2 and 10.4 respectively, compared to dysembryoplastic neuroepithelial tumors. Patients with a duration of epilepsy longer than 10 years had significantly higher chances to show CD34 expression, with an OR of 2.8 compared to those with a duration of epilepsy shorter than 2 years. Furthermore, at univariate analysis CD34 expression appeared significantly related to older age at surgery, higher AEDs intake, and female gender.

CONCLUSIONS: Our study suggests that CD34 expression holds promise as a useful biomolecular marker for LEATs patients, with evidence of a link with clinicopathological features. We confirmed the association between CD34 expression and tumor type and demonstrated a significantly higher probability of CD34 expression in patients with a longer duration of epilepsy, independently of histology.