title: Contrast enhancement in 1p/19q-codeleted anaplastic oligodendrogliomas is associated with 9p loss, genomic instability, and angiogenic gene expression.
abstract: BACKGROUND
  The aim of this study was to correlate MRI features and molecular characteristics in anaplastic oligodendrogliomas (AOs).
  
  
  METHODS
  The MRI characteristics of 50 AO patients enrolled in the French national network for high-grade oligodendroglial tumors were analyzed. The genomic profiles and IDH mutational statuses were assessed using high-resolution single-nucleotide polymorphism arrays and direct sequencing, respectively. The gene expression profiles of 25 1p/19q-codeleted AOs were studied on Affymetrix expression arrays.
  
  
  RESULTS
  Most of the cases were frontal lobe contrast-enhanced tumors (52%), but the radiological presentations of these cases were heterogeneous, ranging from low-grade glioma-like aspects (26%) to glioblastoma-like aspects (22%). The 1p/19q codeletion (n = 39) was associated with locations in the frontal lobe (P = .001), with heterogeneous intratumoral signal intensities (P = .003) and with no or nonmeasurable contrast enhancements (P = .01). The IDH wild-type AOs (n = 7) more frequently displayed ringlike contrast enhancements (P = .03) and were more frequently located outside of the frontal lobe (P = .01). However, no specific imaging pattern could be identified for the 1p/19q-codeleted AO or the IDH-mutated AO. Within the 1p/19q-codeleted AO, the contrast enhancement was associated with larger tumor volumes (P = .001), chromosome 9p loss and CDKN2A loss (P = .006), genomic instability (P = .03), and angiogenesis-related gene expression (P < .001), particularly for vascular endothelial growth factor A and angiopoietin 2.
  
  
  CONCLUSIONS
  In AOs, the 1p/19q codeletion and the IDH mutation are associated with preferential (but not with specific) imaging characteristics. Within 1p/19q-codeleted AO, imaging heterogeneity is related to additional molecular alterations, especially chromosome 9p loss, which is associated with contrast enhancement and larger tumor volume.
authors.affiliation: AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Paris, France (G.R.B., C.D., A.I.); Université Pierre et Marie Curie-Paris 6, Centre de Recherche de l'Institut du Cerveau et de la Moelle Epinière, Paris, France (A.I., C.C.); AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Service de Neuro-radiologie, Paris, France (N.M.-D.); Service de Santé des Armées, Hôpital d'Instruction des Armées, Paris, France (M.L.); Programme Carte d'Identité des Tumeurs, Ligue Nationale Contre le Cancer, Paris, France (E.L.); AP-HM, Hôpital de la Timone, Service de Neuro-Oncologie, Marseille , France (O.C.); CHU Bordeaux, Hôpital Pellegrin, Service de Neurochirurgie, Bordeaux, France (H.L.); Hospices Civils de Lyon, Hôpital Pierre Wertheimer, Service de Neuro-Oncologie, Bron, France (J.H., F.D.); INSERM U1028, CNRS UMR5292, Bron, France (J.H., F.D.); CHU Lille, Hôpital Roger Salengro, Clinique de Neurochirurgie, Lille, France (C.R.); Institut Claudius Regaud, Département de Radiothérapie, Toulouse, France (E.M.); AP-HM, Hôpital de la Timone, Service d'Anatomie Pathologique et de Neuropathologie, Marseille, France (D.F.-B.); Université de la Méditerranée, Aix-Marseille, Faculté de Médecine La Timone, Marseille, France (D.F.B.).
authors.forename: German
authors.initials: G
authors.lastname: Reyes-Botero
authors.forename: Caroline
authors.initials: C
authors.lastname: Dehais
authors.forename: Ahmed
authors.initials: A
authors.lastname: Idbaih
authors.forename: Nadine
authors.initials: N
authors.lastname: Martin-Duverneuil
authors.forename: Marion
authors.initials: M
authors.lastname: Lahutte
authors.forename: Catherine
authors.initials: C
authors.lastname: Carpentier
authors.forename: Eric
authors.initials: E
authors.lastname: Letouzé
authors.forename: Olivier
authors.initials: O
authors.lastname: Chinot
authors.forename: Hugues
authors.initials: H
authors.lastname: Loiseau
authors.forename: Jerome
authors.initials: J
authors.lastname: Honnorat
authors.forename: Carole
authors.initials: C
authors.lastname: Ramirez
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Moyal
authors.forename: Dominique
authors.initials: D
authors.lastname: Figarella-Branger
authors.forename: François
authors.initials: F
authors.lastname: Ducray
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000235:genetics / Q000473:pathology*; D002872:Chromosome Deletion; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics*; D002888:Chromosomes, Human, Pair 19 / Q000235:genetics*; D002899:Chromosomes, Human, Pair 9; D005260:Female; D015870:Gene Expression; D042822:Genomic Instability; D006801:Humans; D007521:Isocitrate Dehydrogenase / Q000235:genetics; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009389:Neovascularization, Pathologic / Q000235:genetics; D009837:Oligodendroglioma / Q000235:genetics / Q000473:pathology*; D020641:Polymorphism, Single Nucleotide; D055815:Young Adult
chemical_list: C538784:IDH2 protein, human; D007521:Isocitrate Dehydrogenase; C543588:IDH1 protein, human
keywords: 1p19q co-deletion; IDH mutation; SNP array; anaplastic oligodendroglioma; magnetic resonance imaging