title: One hundred and one dysembryoplastic neuroepithelial tumors: an adult epilepsy series with immunohistochemical, molecular genetic, and clinical correlations and a review of the literature.
abstract: Simple and complex forms of dysembryoplastic neuroepithelial tumors (DNTs) are readily recognizable but forms with diffuse growth pattern, and hybrid tumors, that is, mixed DNT and ganglioglioma (DNT/GG), are more contentious entities. Rare DNTs have shown aggressive behavior. We reviewed cortical growth patterns, immunophenotype (including CD34, nestin and calbindin), genetic profile, and outcome in 101 DNT in adults. Simple (n = 18), complex (n = 31), diffuse (n = 35) DNT, and mixed DNT/GG (n = 17) showed no difference in age of onset, associated seizure type, or outcome (67.5% free from seizure; mean follow-up, 6 years). CD34 was seen in 61%, calbindin in 57%, and nestin in 86% of all DNT types; these markers were less common in simple DNT. Peritumoral cortical changes (Layer I hypercellularity [61%], satellite nodules [51.6%]) were frequent, but dyslamination (cortical dysplasia) was not identified. Molecular genetic abnormalities identified in 17 cases were IDH1 mutation (n = 3), 1p/19q loss (n = 10), isolated loss 9q (n = 2), and PTEN loss (n = 3), which were not associated with tumor type or location, higher cell proliferation, or distinguishing clinical features (mean age of epilepsy onset, 9 years; age at surgery = 31 years; 69% free from seizure); none had progression on magnetic resonance imaging (mean follow-up, 6 years). No single feature was predictive of seizure-free outcome, but there was a trend for better outcome in CD34-positive tumors (p = 0.07). One case has shown transformation to a higher grade. This study supports the existence of a range of subtypes of DNT some with overlapping features with ganglioglioma; molecular genetic abnormalities were not predictive of atypical behavior.
authors.affiliation: Department of Clinical and Experimental Epilepsy, University College London Institute of Neurology, London, UK. MThom@ion.ucl.ac.uk
authors.forename: Maria
authors.initials: M
authors.lastname: Thom
authors.forename: Ahmed
authors.initials: A
authors.lastname: Toma
authors.forename: Shu
authors.initials: S
authors.lastname: An
authors.forename: Lillian
authors.initials: L
authors.lastname: Martinian
authors.forename: George
authors.initials: G
authors.lastname: Hadjivassiliou
authors.forename: Bernardo
authors.initials: B
authors.lastname: Ratilal
authors.forename: Andrew
authors.initials: A
authors.lastname: Dean
authors.forename: Andrew
authors.initials: A
authors.lastname: McEvoy
authors.forename: Sanjay M
authors.initials: SM
authors.lastname: Sisodiya
authors.forename: Sebastian
authors.initials: S
authors.lastname: Brandner
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D018952:Antigens, CD34 / Q000378:metabolism; D002540:Cerebral Cortex / Q000378:metabolism / Q000473:pathology*; D002648:Child; D004252:DNA Mutational Analysis; D004827:Epilepsy / Q000150:complications* / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D007521:Isocitrate Dehydrogenase / Q000235:genetics*; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D018302:Neoplasms, Neuroepithelial / Q000150:complications / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology*; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009836:Oligodendroglia / Q000378:metabolism / Q000473:pathology; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D018952:Antigens, CD34; D009419:Nerve Tissue Proteins; C538784:IDH2 protein, human; D007521:Isocitrate Dehydrogenase; C543588:IDH1 protein, human