Long-term tumor control and cranial nerve outcomes following Gamma Knife surgery for larger-volume vestibular schwannomas

Clinical article

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Object

Gamma Knife surgery (GKS) for vestibular schwannoma (VS) is an accepted treatment for small- to medium-sized tumors, generally smaller than 2.5 cm in the maximum posterior fossa dimension. The purpose of this study was to evaluate the efficacy and toxicity of GKS for larger tumors.

Methods

Prospectively collected data were analyzed for 22 patients who had undergone GKS for VSs larger than 2.5 cm in the posterior fossa diameter between 1997 and 2006. No patient had symptomatic brainstem compression at the time of GKS. The median treated tumor volume was 9.4 cm3 (range 5.3–19.1 cm3). The median maximum posterior fossa diameter was 2.8 cm (range 2.5–3.8 cm). The median tumor margin dose was 12 Gy (range 12–14 Gy). Serial imaging, audiometry (10 patients with serviceable hearing pre-GKS), and clinical follow-up were available for a median of 66 months (range 26–121 months). Tumor control failure was defined as either a progressive increase in tumor diameter of at least 2 mm in any dimension or a later resection.

Results

Four patients met the criteria for GKS failure, including 1 patient who demonstrated sarcomatous degeneration more than 7 years after GKS and died 3 months after microsurgical debulking. An enlarging cystic component was the surgical indication in 1 of the 2 patients who required resection, although 27% of tumors (6 lesions) were cystic before GKS. The 3-year actuarial rate of tumor control, freedom from new facial neuropathy, and preservation of functional hearing were 86%, 92%, and 47%, respectively. At 5 years post-GKS, these rates decreased to 82%, 85%, and 28%, respectively. At the most recent follow-up, 91% of tumors were smaller than at the time of GKS and the median maximum posterior fossa diameter reduction was 26%. On multivariate analysis, none of the following factors was associated with GKS failure, new facial weakness, new trigeminal neuropathy, or loss of serviceable hearing: patient age, tumor volume, tumor margin dose, and preoperative cranial nerve dysfunction.

Conclusions

Single-session radiosurgery is a successful treatment for the majority of patients with larger VSs. Although tumor control rates are lower than those for smaller VSs managed with GKS, the cranial nerve morbidity of GKS is significantly lower than that typically achieved via resection of larger VSs.

Abbreviations used in this paper: AAO-HNS = American Academy of Otolaryngology–Head and Neck Surgery; CN = cranial nerve; GKS = Gamma Knife surgery; GTR = gross-total resection; HB = House-Brackmann; NTR = near-total resection; PFS = progression-free survival; STR = subtotal resection; VP = ventriculoperitoneal; VS = vestibular schwannoma.

Article Information

Address correspondence to: Michael J. Link, M.D., Department of Neurologic Surgery, Mayo Clinic, 200 First Street SW, Rochester, Minnesota 55905. email: link.michael@mayo.edu.

Please include this information when citing this paper: published online December 16, 2011; DOI: 10.3171/2011.11.JNS11811.

© AANS, except where prohibited by US copyright law.

Headings

Figures

  • View in gallery

    Representative axial Gd-enhanced T1-weighted MR images from 2 cases of large VSs treated with primary GKS due to patient preference (A and B) or multiple medical comorbidities (C and D). Pre-GKS image (A) obtained in a 65-year-old man with AAO-HNS Class B hearing and HB Grade I facial nerve function on the right, showing a 3.2-cm VS with documented growth over time. The patient was treated with 12 Gy to the 50% isodose line to a volume of 11.1 cm3. Image (B) obtained 84 months after GKS, showing a tumor now measuring 1.8 cm. The patient retained HB Grade I facial function and Class B hearing without any new symptoms. Pre-GKS image (C) obtained in a 65-year-old woman with AAO-HNS Class D hearing on the right and mild ataxia with resulting falls, showing a 3.8-cm cystic VS. This patient was treated with 12 Gy to the 50% isodose line to a volume of 8.2 cm3. Image (D) obtained 1 year after GKS, showing a cystic component that has grown. The tumor now measures 4.7 cm in overall dimension. Worsening ataxia developed, as did intractable nausea and vomiting. The patient also suffered an ankle fracture after a fall. She underwent excision of the cyst and subtotal tumor removal. Postoperatively, her gait and nausea improved. She retained the HB Grade II facial function she had had before GKS.

  • View in gallery

    Actuarial tumor control curve for 22 patients with large VSs treated with GKS. The number of patients still at risk for tumor progression at each time point appears in parentheses.

  • View in gallery

    Actuarial curve illustrating the preservation of pre-GKS HB grade over time. The number of patients still at risk for suffering facial weakness at each time point appears in parentheses.

  • View in gallery

    Actuarial curve demonstrating hearing preservation in 10 patients who had serviceable hearing (AAO-HNS Class A/B) before GKS to treat a larger VS. The number of patients still at risk for suffering hearing loss at each time point appears in parentheses.

References

  • 1

    Anderson DELeonetti JWind JJCribari DFahey K: Resection of large vestibular schwannomas: facial nerve preservation in the context of surgical approach and patient-assessed outcome. J Neurosurg 102:6436492005

    • Search Google Scholar
    • Export Citation
  • 2

    Anonymous: Committee on Hearing and Equilibrium guidelines for the evaluation of hearing preservation in acoustic neuroma (vestibular schwannoma). American Academy of Otolaryngology-Head and Neck Surgery Foundation, INC. Otolaryngol Head Neck Surg 113:1791801995

    • Search Google Scholar
    • Export Citation
  • 3

    Bloch DCOghalai JSJackler RKOsofsky MPitts LH: The fate of the tumor remnant after less-than-complete acoustic neuroma resection. Otolaryngol Head Neck Surg 130:1041122004

    • Search Google Scholar
    • Export Citation
  • 4

    Chihara YIto KSugasawa KShin M: Neurological complications after acoustic neurinoma radiosurgery: revised risk factors based on long-term follow-up. Acta Otolaryngol 127:Suppl 55965702007

    • Search Google Scholar
    • Export Citation
  • 5

    Di Maio SAkagami R: Prospective comparison of quality of life before and after observation, radiation, or surgery for vestibular schwannomas. Clinical article. J Neurosurg 111:8558622009

    • Search Google Scholar
    • Export Citation
  • 6

    Di Maio SMalebranche ADWesterberg BAkagami R: Hearing preservation after microsurgical resection of large vestibular schwannomas. Neurosurgery 68:6326402011

    • Search Google Scholar
    • Export Citation
  • 7

    Fahlbusch RNeu MStrauss C: Preservation of hearing in large acoustic neurinomas following removal via suboccipitolateral approach. Acta Neurochir (Wien) 140:7717781998

    • Search Google Scholar
    • Export Citation
  • 8

    Flickinger JCKondziolka DNiranjan ALunsford LD: Results of acoustic neuroma radiosurgery: an analysis of 5 years' experience using current methods. J Neurosurg 94:162001

    • Search Google Scholar
    • Export Citation
  • 9

    Flickinger JCKondziolka DNiranjan AMaitz AVoynov GLunsford LD: Acoustic neuroma radiosurgery with marginal tumor doses of 12 to 13 Gy. Int J Radiat Oncol Biol Phys 60:2252302004

    • Search Google Scholar
    • Export Citation
  • 10

    Foote RLCoffey RJSwanson JWHarner SGBeatty CWKline RW: Stereotactic radiosurgery using the gamma knife for acoustic neuromas. Int J Radiat Oncol Biol Phys 32:115311601995

    • Search Google Scholar
    • Export Citation
  • 11

    Frerebeau PBenezech JUziel ACoubes PSegnarbieux FMalonga M: Hearing preservation after acoustic neurinoma operation. Neurosurgery 21:1972001987

    • Search Google Scholar
    • Export Citation
  • 12

    Friedman RABrackmann DEHitselberger WESchwartz MSIqbal ZBerliner KI: Surgical salvage after failed irradiation for vestibular schwannoma. Laryngoscope 115:182718322005

    • Search Google Scholar
    • Export Citation
  • 13

    Godefroy WPvan der Mey AGde Bruine FTHoekstra ERMalessy MJ: Surgery for large vestibular schwannoma: residual tumor and outcome. Otol Neurotol 30:6296342009

    • Search Google Scholar
    • Export Citation
  • 14

    Hasegawa TFujitani SKatsumata SKida YYoshimoto MKoike J: Stereotactic radiosurgery for vestibular schwannomas: analysis of 317 patients followed more than 5 years. Neurosurgery 57:2572652005

    • Search Google Scholar
    • Export Citation
  • 15

    House JWBrackmann DE: Facial nerve grading system. Otolaryngol Head Neck Surg 93:1461471985

  • 16

    Iwai YYamanaka KIshiguro T: Surgery combined with radiosurgery of large acoustic neuromas. Surg Neurol 59:2832912003

  • 17

    Iwai YYamanaka KYamagata KYasui T: Surgery after radiosurgery for acoustic neuromas: surgical strategy and histological findings. Neurosurgery 60:2 Suppl 1ONS75ONS822007

    • Search Google Scholar
    • Export Citation
  • 18

    Karpinos MTeh BSZeck OCarpenter LSPhan CMai WY: Treatment of acoustic neuroma: stereotactic radiosurgery vs. microsurgery. Int J Radiat Oncol Biol Phys 54:141014212002

    • Search Google Scholar
    • Export Citation
  • 19

    Kondziolka DLunsford LDFlickinger JC: Acoustic tumors: operation versus radiation—making sense of opposing viewpoints. Part II. Acoustic neuromas: sorting out management options. Clin Neurosurg 50:3133282003

    • Search Google Scholar
    • Export Citation
  • 20

    Kondziolka DLunsford LDMcLaughlin MRFlickinger JC: Long-term outcomes after radiosurgery for acoustic neuromas. N Engl J Med 339:142614331998

    • Search Google Scholar
    • Export Citation
  • 21

    Lanman THBrackmann DEHitselberger WESubin B: Report of 190 consecutive cases of large acoustic tumors (vestibular schwannoma) removed via the translabyrinthine approach. J Neurosurg 90:6176231999

    • Search Google Scholar
    • Export Citation
  • 22

    Limb CJLong DMNiparko JK: Acoustic neuromas after failed radiation therapy: challenges of surgical salvage. Laryngoscope 115:93982005

    • Search Google Scholar
    • Export Citation
  • 23

    Lunsford LDNiranjan AFlickinger JCMaitz AKondziolka D: Radiosurgery of vestibular schwannomas: summary of experience in 829 cases. J Neurosurg 102:Suppl1951992005

    • Search Google Scholar
    • Export Citation
  • 24

    Massager NNissim ODelbrouck CDelpierre IDevriendt DDesmedt F: Irradiation of cochlear structures during vestibular schwannoma radiosurgery and associated hearing outcome. J Neurosurg 107:7337392007

    • Search Google Scholar
    • Export Citation
  • 25

    Myrseth EMøller PPedersen PHLund-Johansen M: Vestibular schwannoma: surgery or gamma knife radiosurgery? A prospective, nonrandomized study. Neurosurgery 64:6546632009

    • Search Google Scholar
    • Export Citation
  • 26

    Myrseth EMøller PPedersen PHVassbotn FSWentzel-Larsen TLund-Johansen M: Vestibular schwannomas: clinical results and quality of life after microsurgery or gamma knife radiosurgery. Neurosurgery 56:9279352005

    • Search Google Scholar
    • Export Citation
  • 27

    Nicoucar KMomjian SVader JPDe Tribolet N: Surgery for large vestibular schwannomas: how patients and surgeons perceive quality of life. J Neurosurg 105:2052122006

    • Search Google Scholar
    • Export Citation
  • 28

    Park CKJung HWKim JESon YJPaek SHKim DG: Therapeutic strategy for large vestibular schwannomas. J Neurooncol 77:1671712006

    • Search Google Scholar
    • Export Citation
  • 29

    Pollock BEDriscoll CLFoote RLLink MJGorman DABauch CD: Patient outcomes after vestibular schwannoma management: a prospective comparison of microsurgical resection and stereotactic radiosurgery. Neurosurgery 59:77852006

    • Search Google Scholar
    • Export Citation
  • 30

    Pollock BELunsford LDKondziolka DFlickinger JCBissonette DJKelsey SF: Outcome analysis of acoustic neuroma management: a comparison of microsurgery and stereotactic radiosurgery. Neurosurgery 36:2152291995

    • Search Google Scholar
    • Export Citation
  • 31

    Pollock BELunsford LDKondziolka DSekula RSubach BRFoote RL: Vestibular schwannoma management. Part II. Failed radiosurgery and the role of delayed microsurgery. J Neurosurg 89:9499551998

    • Search Google Scholar
    • Export Citation
  • 32

    Raftopoulos CAbu Serieh BDuprez TDocquier MAGuérit JM: Microsurgical results with large vestibular schwannomas with preservation of facial and cochlear nerve function as the primary aim. Acta Neurochir (Wien) 147:6977062005

    • Search Google Scholar
    • Export Citation
  • 33

    Ramina RCoelho Neto MBordignon KCMattei TClemente RPires Aguiar PH: Treatment of large and giant residual and recurrent vestibular schwannomas. Skull Base 17:1091172007

    • Search Google Scholar
    • Export Citation
  • 34

    Régis JPellet WDelsanti CDufour HRoche PHThomassin JM: Functional outcome after gamma knife surgery or microsurgery for vestibular schwannomas. J Neurosurg 97:109111002002

    • Search Google Scholar
    • Export Citation
  • 35

    Roland JT JrFishman AJGolfinos JGCohen NAlexiades GJackman AH: Cranial nerve preservation in surgery for large acoustic neuromas. Skull Base 14:85912004

    • Search Google Scholar
    • Export Citation
  • 36

    Samii MMatthies C: Management of 1000 vestibular schwannomas (acoustic neuromas): hearing function in 1000 tumor resections. Neurosurgery 40:2482621997

    • Search Google Scholar
    • Export Citation
  • 37

    Schmitt WRCarlson MLGiannini CDriscoll CLLink MJ: Radiation-induced sarcoma in a large vestibular schwannoma following stereotactic radiosurgery: case report. Neurosurgery 68:E840E8462011

    • Search Google Scholar
    • Export Citation
  • 38

    van de Langenberg Rde Bondt BJNelemans PJBaumert BGStokroos RJ: Follow-up assessment of vestibular schwannomas: volume quantification versus two-dimensional measurements. Neuroradiology 51:5175242009

    • Search Google Scholar
    • Export Citation
  • 39

    van Roijen LNijs HGAvezaat CJKarlsson GLinquist CPauw KH: Costs and effects of microsurgery versus radiosurgery in treating acoustic neuroma. Acta Neurochir (Wien) 139:9429481997

    • Search Google Scholar
    • Export Citation
  • 40

    Yang HCKano HAwan NRLunsford LDNiranjan AFlickinger JC: Gamma Knife radiosurgery for larger-volume vestibular schwannomas. Clinical article. J Neurosurg 114:8018072011

    • Search Google Scholar
    • Export Citation

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