IDH mutations but not TERTp mutations are associated with seizures in lower-grade gliomas.

Glioma is the most common malignant tumor in the central nervous system (CNS). Lower-grade gliomas (LGG) refer to Grade II and III gliomas. In LGG patients, seizure often appears as an initial symptom and play an important role in clinical performance and quality of life of the patients. To date, the relationship between the onset of seizures and the molecular pathology in gliomas is still poorly investigated. In this study, we investigate the potential relationship between isocitrate dehydrogenase (IDH)/telomerase reverse transcriptase promoter (TERTp) mutations and preoperative seizures in patients with LGG. 289 adult LGG patients were enrolled in this study. Data of clinical characteristics and molecular pathology were acquired. Sanger sequencing was used to detect IDH/TERTp mutations. Chi-square test was performed to determine if the IDH/TERTp mutations were associated with seizures and seizure types. In 289 LGG patients, preoperative seizures accounted for 25.3% (73/289), IDH mutations accounted for 34.3%(99/289), and TERTp mutations accounted for 44.3% (128/289). The correlation analysis demonstrated that IDH mutation is a significant factor influencing the occurrence of tumor-related epilepsy (P <.001, chi-square test). On the other hand, the statistical analysis revealed no significant correlation between TERTp mutations and seizure in LGG patients (P = .102, chi-square test). The tumor-related epilepsy rates vary among different subgroups according to IDH/TERTp mutations. However, there is no definite correlation between the IDH (P = 1.000, chi-square test)/TERTp (P = .613, chi-square test) mutations and the types of epileptic seizure. IDH mutations are more common in preoperative LGG patients with epileptic symptoms, suggesting that this mutation is positively correlated with seizures. However, there was no significant correlation between TERTp mutations and seizures. Different molecular pathologic types based on IDH/TERTp have different incidences of tumor-associated epilepsy in LGGs.