Gamma Knife Radiosurgery vs Initial Conservative Treatment for Vestibular Schwannoma Patients With Preserved Hearing, a Prospective Randomized Study

Study Overview
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Brief Summary
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The effect of Gamma knife radiosurgery (GKRS) on hearing loss, in patients with vestibular schwannoma (VS) and preserved hearing is still unclear. Retrospective data indicate that the hearing is preserved in most patient years after the gamma knife treatment. Recent prospective data suggests that radiosurgery could be a hearing preserving treatment for these patients. The main objective of this study is to evaluate if GKRS can inhibit progression of hearing loss in patients with VS. Patients with preserved hearing will be offered to participate in the study and randomized ether to GKRS or initial conservative treatment for their vestibular schwannoma. They will then be followed with scheduled magnetic resonance image(MRI) and audiometry and evaluated after one, three and five years after treatment.

Official Title
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Gamma Knife Radiosurgery vs Initial Conservative Treatment for Vestibular Schwannoma Patients With Preserved Hearing, a Prospective Randomized Study

Conditions
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Vestibular Schwannoma

Intervention / Treatment
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* Radiation: Initial Gamma knife radiosurgery


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients newly (<6 months) diagnosed with Vestibular schwannoma less than 20 mm in diameter. Vestibular schwannoma with or without evidence of growth. Patients between 18 and 80 years of age. Karnofsky performance score >70 Patients with vestibular schwannoma and preserved hearing according to Gardner Robertson class 1-2, and speech discrimination (SD) scores between 50-100% will participate in the hearing preservation part of the study. - Exclusion Criteria: 1. Patients with Neurofibromatosis type 2 will be excluded to achieve a homogenous study population. 2. Patients who had other treatments prior to the GKRS (usually microsurgery (MS), GKRS or external beam radiation) for their tumour will also be excluded for the same reason. 3. Patients who are not citizens in the country where they will be followed will be excluded, to reassure the same follow up within the study population. 4. Hearing loss due injury or to active ear disease, such as Meniere´s disease, otosclerosis or chronic otitis media. 5. Patients with poor comprehension of the the language in the country where they are followed, such that adequate performance on speech tests, are unlikely. 6. Claustrophobia, making MR follow up impossible without sedation. 7. Alcohol- or narcotic abuses that effect compliance to the follow up. 8. Uncontrolled neoplastic disease.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Initial Gamma knife<br>Patients with VS and preserved hearing, randomized to initial gamma knife radiosurgery will receive this treatment within a few months after enrollment | Radiation: Initial Gamma knife radiosurgery<br> <br> |
| No Intervention: Initial conservative<br>Patients with VS and preserved hearing, randomized to initial conservative treatment will initially be followed with repeated MRI and audiometry. If MRI show progression of VS requiring intervention, patients will receive treatment but still belong to the initial treatment arm, according to intention to treat. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The numbers of participants with preserve hearing | Baseline audiometric investigation will be performed at time of enrollment. Patients will be followed with audiometric investigations after 1, 3 and 5 years after gamma knife or conservative treatment.Primary endpoint will be numbers of patients with preserve hearing for each treatment arm. | up to five years after enrollment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Tumor control | MR investigation including digitalized volumetric of vestibular schwannomas will be performed | 1, 2, 5 years after enrollment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vestibular schwannoma, Gamma knife radiosurgery, Hearing preservation