Pre- and Post-surgical Poor Seizure Control as Hallmark of Malignant Progression in Patients With Glioma?

Giada Pauletto; Annacarmen Nilo; Christian Lettieri; Lorenzo Verriello; Barbara Tomasino; Gian Luigi Gigli; Miran Skrap; Tamara Ius

doi:10.3389/fneur.2022.890857

Pre- and Post-surgical Poor Seizure Control as Hallmark of Malignant Progression in Patients With Glioma?

Front Neurol. 2022 May 16:13:890857. doi: 10.3389/fneur.2022.890857. eCollection 2022.

Authors

Giada Pauletto¹, Annacarmen Nilo², Christian Lettieri¹, Lorenzo Verriello¹, Barbara Tomasino³, Gian Luigi Gigli², Miran Skrap⁴, Tamara Ius⁴

Affiliations

¹ Neurology Unit, S. Maria della Misericordia University Hospital, Udine, Italy.
² Clinical Neurology Unit, S. Maria della Misericordia University Hospital, Udine, Italy.
³ Scientific Institute, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) E. Medea, Dipartimento/Unità Operativa Pasian di Prato, Udine, Italy.
⁴ Neurosurgery Unit, S. Maria della Misericordia University Hospital, Udine, Italy.

Abstract

Background: Regarding brain tumor-related epilepsy (BTRE), there is an increasing number of evidence about a relationship between epileptogenesis and oncogenesis. A recent study suggests a role of post-surgery seizure outcome on the survival of patients with low-grade glioma (LGG), underlying the need for a targeted and aggressive epilepsy treatment.

Objective: This study aims at investigating the possible correlation between pre- and post-surgical seizure control and tumor progression in patients who underwent surgery for LGG.

Methods: We performed a retrospective analysis of patients affected by LGGs and BTRE, in a single high-volume neurosurgical center. Seizure control was assessed before surgery and at 3 years of follow-up. Patients with histological progression in high-grade glioma (HGG) have been evaluated. Clinical features, pre-surgical electroencephalograms (EEGs), and electrocorticography (ECoG) have been analyzed.

Results: Among 154 subjects, we collected 32 patients who presented a tumor progression in HGG during the follow-up period. The majority had poor seizure control both pre- and post-surgery, never being in Engel class Ia throughout the whole history of their disease. Almost all patients with poor seizure control had pathological ECoG recording. Clinical features of seizures did not correlate with seizure outcome. On the univariate analysis, the age, the post-operative Engel class, and the extent of resection (EOR) were the prognostic factors significantly associated with oncological outcome; nevertheless, on multivariate analysis, Engel class significance was not confirmed, and the only predicting factor were age and EOR.

Conclusions: Although not confirmed on multivariate analysis, post-surgical seizure control could be a relevant factor to consider during follow-up of BRTE, in particular, when gross total resection is not achieved. Pathological findings on the ECoG may suggest a "hidden" propensity to malignant progression, strictly related to the persistent neuronal hyper-excitability. Further studies with longer follow-up period are needed to confirm our observations.

Keywords: brain-tumor epilepsy; electrocorticography; low-grade glioma; malignant progression; seizure outcome.