title: Multimodal MR imaging (diffusion, perfusion, and spectroscopy): is it possible to distinguish oligodendroglial tumor grade and 1p/19q codeletion in the pretherapeutic diagnosis?
abstract: OBJECTIVE
  Pretherapeutic determination of tumor grade and genotype in grade II and III oligodendroglial tumors is clinically important but is still challenging. Tumor grade and 1p/19q status are currently the 2 most important factors in therapeutic decision making for patients with these tumors. Histopathology and cMRI studies are still limited in some cases. In the present study, we were interested in determining whether the combination of PWI, DWI, and MR spectroscopy could help distinguish oligodendroglial tumors according to their histopathologic grade and genotype.
  
  
  METHODS
  We retrospectively reviewed 50 adult patients with grade II and III oligodendrogliomas and oligoastrocytomas who had DWI, PWI, and MR spectroscopy at short and long TE data and known 1p/19q status. Univariate analyses and multivariate random forest models were performed to determine which criteria could differentiate between grades and genotypes.
  
  
  RESULTS
  ADC, rCBV, rCBF, and rK2 were significantly different between grade II and III oligodendroglial tumors. DWI, PWI, and MR spectroscopy showed no significant difference between tumors with and without 1p/19q loss. Separation between tumor grades and genotypes with cMRI alone showed 31% and 48% misclassification rates, respectively. Multimodal MR imaging helps to determine tumor grade and 1p/19q genotype more accurately (misclassification rates of 17% and 40%, respectively).
  
  
  CONCLUSIONS
  Although multimodal investigation of oligodendroglial tumors has a lower contribution to 1p/19q genotyping compared with cMRI alone, it greatly improves the accuracy of grading of these neoplasms. Use of multimodal MR imaging could thus provide valuable information that may assist clinicians in patient preoperative management and treatment decision making.
authors.affiliation: Centre de Résonance Magnétique Biologique et Médicale, Aix-Marseille University, Marseille, France. slim.fellah@univ-amu.fr
authors.forename: S
authors.initials: S
authors.lastname: Fellah
authors.forename: D
authors.initials: D
authors.lastname: Caudal
authors.forename: A M
authors.initials: AM
authors.lastname: De Paula
authors.forename: P
authors.initials: P
authors.lastname: Dory-Lautrec
authors.forename: D
authors.initials: D
authors.lastname: Figarella-Branger
authors.forename: O
authors.initials: O
authors.lastname: Chinot
authors.forename: P
authors.initials: P
authors.lastname: Metellus
authors.forename: P J
authors.initials: PJ
authors.lastname: Cozzone
authors.forename: S
authors.initials: S
authors.lastname: Confort-Gouny
authors.forename: B
authors.initials: B
authors.lastname: Ghattas
authors.forename: V
authors.initials: V
authors.lastname: Callot
authors.forename: N
authors.initials: N
authors.lastname: Girard
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001254:Astrocytoma / Q000175:diagnosis / Q000235:genetics; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000235:genetics; D002540:Cerebral Cortex / Q000473:pathology; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics*; D002888:Chromosomes, Human, Pair 19 / Q000235:genetics*; D003287:Contrast Media; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D005625:Frontal Lobe / Q000473:pathology; D005838:Genotype; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007091:Image Processing, Computer-Assisted / Q000379:methods; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009837:Oligodendroglioma / Q000175:diagnosis* / Q000235:genetics; D012189:Retrospective Studies; D017384:Sequence Deletion / Q000235:genetics*; D013702:Temporal Lobe / Q000473:pathology; D055815:Young Adult
chemical_list: D003287:Contrast Media