Surgical assessment of the insula. Part 2: validation of the Berger-Sanai zone classification system for predicting extent of glioma resection

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OBJECT

Though challenging, maximal safe resection of insular gliomas enhances overall and progression-free survival and deters malignant transformation. Previously published reports have shown that surgery can be performed with low morbidity. The authors previously described a Berger-Sanai zone classification system for insular gliomas. Using a subsequent dataset, they undertook this study to validate this zone classification system for predictability of extent of resection (EOR) in patients with insular gliomas.

METHODS

The study population included adults who had undergone resection of WHO Grade II, III, or IV insular gliomas. In accordance with our prior published report, tumor location was classified according to the Berger-Sanai quadrant-style classification system into Zones I through IV. Interobserver variability was analyzed using a cohort of newly diagnosed insular gliomas and independent classification scores given by 3 neurosurgeons at various career stages. Glioma volumes were analyzed using FLAIR and T1-weighted contrast-enhanced MR images.

RESULTS

One hundred twenty-nine procedures involving 114 consecutive patients were identified. The study population from the authors’ previously published experience included 115 procedures involving 104 patients. Thus, the total experience included 244 procedures involving 218 patients with insular gliomas treated at the authors’ institution. The most common presenting symptoms were seizure (68.2%) and asymptomatic recurrence (17.8%). WHO Grade II glioma histology was the most common (54.3%), followed by Grades III (34.1%) and IV (11.6%). The median tumor volume was 48.5 cm3. The majority of insular gliomas were located in the anterior portion of the insula with 31.0% in Zone I, 10.9% in Zone IV, and 16.3% in Zones I+IV. The Berger-Sanai zone classification system was highly reliable, with a kappa coefficient of 0.857. The median EOR for all zones was 85%. Comparison of EOR between the current and prior series showed no change and Zone I gliomas continue to have the highest median EOR. Short- and long-term neurological complications remain low, and zone classification correlated with short-term complications, which were highest in Zone I and in Giant insular gliomas.

CONCLUSIONS

The previously proposed Berger-Sanai classification system is highly reliable and predictive of insular glioma EOR and morbidity.

ABBREVIATIONSEOR = extent of resection; FLAIR = fluid-attenuated inversion recovery; IDH = isocitrate dehydrogenase; WHO = World Health Organization.
Article Information

Contributor Notes

Correspondence Shawn L. Hervey-Jumper, Department of Neurological Surgery, University of California, San Francisco, 505 Parnassus Ave., M779, San Francisco, CA 94143. email: herveyju@umich.edu.INCLUDE WHEN CITING Published online September 4, 2015; DOI: 10.3171/2015.4.JNS1521.Disclosure The authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper.

© Copyright 1944-2019 American Association of Neurological Surgeons

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References
  • 1

    Beiko JSuki DHess KRFox BDCheung VCabral M: IDH1 mutant malignant astrocytomas are more amenable to surgical resection and have a survival benefit associated with maximal surgical resection. Neuro Oncol 16:81912014

    • Search Google Scholar
    • Export Citation
  • 2

    Duffau H: Surgery of low-grade gliomas: towards a ‘functional neurooncology. Curr Opin Oncol 21:5435492009

  • 3

    Duffau HMoritz-Gasser SGatignol P: Functional outcome after language mapping for insular World Health Organization Grade II gliomas in the dominant hemisphere: experience with 24 patients. Neurosurg Focus 27:2E72009

    • Search Google Scholar
    • Export Citation
  • 4

    Gozé CRigau VGibert LMaudelonde TDuffau H: Lack of complete 1p19q deletion in a consecutive series of 12 WHO grade II gliomas involving the insula: a marker of worse prognosis?. J Neurooncol 91:152009

    • Search Google Scholar
    • Export Citation
  • 5

    Griessenauer CJMiller JHAgee BSFisher WS IIICuré JKChapman PR: Observer reliability of arteriovenous malformations grading scales using current imaging modalities. J Neurosurg 120:117911872014

    • Search Google Scholar
    • Export Citation
  • 6

    Ius TPauletto GIsola MGregoraci GBudai RLettieri C: Surgery for insular low-grade glioma: predictors of postoperative seizure outcome. J Neurosurg 120:12232014

    • Search Google Scholar
    • Export Citation
  • 7

    Kim YHKim CY: Current surgical management of insular gliomas. Neurosurg Clin N Am 23:199206vii2012

  • 8

    Lang FFOlansen NEDeMonte FGokaslan ZLHolland ECKalhorn C: Surgical resection of intrinsic insular tumors: complication avoidance. J Neurosurg 95:6386502001

    • Search Google Scholar
    • Export Citation
  • 9

    Mehrkens JHKreth FWMuacevic AOstertag CB: Long term course of WHO grade II astrocytomas of the Insula of Reil after I-125 interstitial irradiation. J Neurol 251:145514642004

    • Search Google Scholar
    • Export Citation
  • 10

    Moshel YAMarcus JDParker ECKelly PJ: Resection of insular gliomas: the importance of lenticulostriate artery position. J Neurosurg 109:8258342008

    • Search Google Scholar
    • Export Citation
  • 11

    Pallud JAudureau EBlonski MSanai NBauchet LFontaine D: Epileptic seizures in diffuse low-grade gliomas in adults. Brain 137:4494622014

    • Search Google Scholar
    • Export Citation
  • 12

    Sanai NMirzadeh ZBerger MS: Functional outcome after language mapping for glioma resection. N Engl J Med 358:18272008

  • 13

    Sanai NPolley MYBerger MS: Insular glioma resection: assessment of patient morbidity, survival, and tumor progression. J Neurosurg 112:192010

    • Search Google Scholar
    • Export Citation
  • 14

    Skrap MMondani MTomasino BWeis LBudai RPauletto G: Surgery of insular nonenhancing gliomas: volumetric analysis of tumoral resection, clinical outcome, and survival in a consecutive series of 66 cases. Neurosurgery 70:108110942012

    • Search Google Scholar
    • Export Citation
  • 15

    Vanaclocha VSáiz-Sapena NGarcía-Casasola C: Surgical treatment of insular gliomas. Acta Neurochir (Wien) 139:112611351997

  • 16

    Wu AAldape KLang FF: High rate of deletion of chromosomes 1p and 19q in insular oligodendroglial tumors. J Neurooncol 99:57642010

    • Search Google Scholar
    • Export Citation
  • 17

    Wu ASWitgert MELang FFXiao LBekele BNMeyers CA: Neurocognitive function before and after surgery for insular gliomas. J Neurosurg 115:111511252011

    • Search Google Scholar
    • Export Citation
  • 18

    Yaşargil MGvon Ammon KCavazos EDoczi TReeves JDRoth P: Tumours of the limbic and paralimbic systems. Acta Neurochir (Wien) 118:40521992

    • Search Google Scholar
    • Export Citation
  • 19

    Zentner JMeyer BStangl ASchramm J: Intrinsic tumors of the insula: a prospective surgical study of 30 patients. J Neurosurg 85:2632711996

    • Search Google Scholar
    • Export Citation
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