title: Supratentorial low-grade glioma resectability: statistical predictive analysis based on anatomic MR features and tumor characteristics.
abstract: OBJECTIVE
  To retrospectively assess the main variables that affect the complete magnetic resonance (MR) imaging-guided resection of supratentorial low-grade gliomas.
  
  
  METHODS
  Institutional review board approval was obtained for this retrospective HIPAA-compliant study, with the requirement for informed consent waived. Data from 101 patients (61 men, 40 women; mean age, 39 years; age range, 18-72 years) who had nonenhancing supratentorial mass lesions that were histopathologically diagnosed as low-grade (World Health Organization grade II) gliomas and consecutively underwent surgery with intraoperative MR imaging guidance were analyzed. There were 21 low-grade astrocytomas, 64 oligodendrogliomas, and 16 mixed oligoastrocytomas. Initial and residual tumor volumes were measured on intraoperative T2-weighted MR images and three-dimensional spoiled gradient-echo MR images. The anatomic relationships between the tumor and eloquent cortical and/or subcortical regions and the influence of these relationships on the extent of resection were analyzed on the basis of preoperative MR imaging findings. Summary measures, univariate Fisher exact test and t test, and multivariate logistic regression analyses were performed.
  
  
  RESULTS
  Tumor volume ranged from 2.7-231.0 mL. Univariate analyses revealed the following tumor characteristics to be significant predictive variables of incomplete tumor resection: diffuse tumor margin on T2-weighted MR images, oligodendroglioma or oligoastrocytoma histopathologic type, and large tumor volume (P < .05 for all). Tumor involvement of the following structures was associated with incomplete resection: corpus callosum, corticospinal tract, insular lobe, middle cerebral artery, motor cortex, optic radiation, visual cortex, and basal ganglia (P < .05 for all). Multivariate analyses revealed that incomplete tumor resection was due to tumor involvement of the corticospinal tract (P < .01), large tumor volume (P < .01), and oligodendroglioma histopathologic type (P = .02).
  
  
  CONCLUSIONS
  The main variables associated with incomplete tumor resection in 101 patients were identified by using statistical predictive analyses.
authors.affiliation: Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Ion-Florin
authors.initials: IF
authors.lastname: Talos
authors.forename: Kelly H
authors.initials: KH
authors.lastname: Zou
authors.forename: Lucila
authors.initials: L
authors.lastname: Ohno-Machado
authors.forename: Jui G
authors.initials: JG
authors.lastname: Bhagwat
authors.forename: Ron
authors.initials: R
authors.lastname: Kikinis
authors.forename: Peter M
authors.initials: PM
authors.lastname: Black
authors.forename: Ferenc A
authors.initials: FA
authors.lastname: Jolesz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005910:Glioma / Q000473:pathology* / Q000601:surgery*; D006801:Humans; D007430:Intraoperative Care; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D015173:Supratentorial Neoplasms / Q000473:pathology* / Q000601:surgery*