title: Genetic features of oligodendrogliomas and presence of seizures. The relationship of seizures and genetics in LGOs.
abstract: Low grade oligodendrogliomas (LGO) are diffusely infiltrating World Health Organization (WHO) grade II gliomas, 20 - 30% of which show contrast enhancement. Seizures are a common presenting feature. It has been suggested that 1p19q co-deletion is associated with occurrence of seizures in adults, however, to date, the relationship of tumor genetics and seizure activity has not been extensively investigated. We sought to assess the influence of 1p19q co-deletion, IDH1-R132H positivity, and radiological variables on seizure activity in LGO patients. Specifically, we examined whether these characteristics were associated with seizure at initial presentation, or if they could predict outcome in terms of seizure free survival. In 62 LGOs, neither tumor location nor tumor enhancement were associated with seizures. 1p19q co-deletion status did not predict seizures when controlled for mutant IDH1-R132H expression, tumor location, or enhancement status (odds ratio (OR) 0.9, 95% confidence interval (CI) 0.1 - 4.3). This study, although of limited statistical power, did not demonstrate an association between 1p19q status and seizure occurrence in LGO's. Replication in a larger cohort would further support our hypothesis that 1p19q status alone cannot be used as a reliable predictor of seizure occurrence in LGO's.
authors.affiliation: Department of Neuropathology, Department of Radiology, Department of Neurology, Beaumont Hospital, Beaumont, Dublin, Department of Statistics, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin, and Department of Neurosurgery, Beaumont Hospital, Beaumont, Dublin, Ireland.
authors.forename: Linda
authors.initials: L
authors.lastname: Mulligan
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Ryan
authors.forename: Margaret
authors.initials: M
authors.lastname: O'Brien
authors.forename: Seamus
authors.initials: S
authors.lastname: Looby
authors.forename: Josephine
authors.initials: J
authors.lastname: Heffernan
authors.forename: Joanne
authors.initials: J
authors.lastname: O'Sullivan
authors.forename: Mary
authors.initials: M
authors.lastname: Clarke
authors.forename: Patrick
authors.initials: P
authors.lastname: Buckley
authors.forename: David
authors.initials: D
authors.lastname: O'Brien
authors.forename: Michael
authors.initials: M
authors.lastname: Farrell
authors.forename: Francesca Mary
authors.initials: FM
authors.lastname: Brett
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000235:genetics* / Q000473:pathology; D002872:Chromosome Deletion; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics*; D005260:Female; D006801:Humans; D017403:In Situ Hybridization; D017404:In Situ Hybridization, Fluorescence; D007521:Isocitrate Dehydrogenase / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009837:Oligodendroglioma / Q000235:genetics* / Q000473:pathology; D012640:Seizures / Q000235:genetics*; D055815:Young Adult
chemical_list: D007521:Isocitrate Dehydrogenase; C543588:IDH1 protein, human