Fractionated stereotactic radiosurgery for the treatment of meningiomas

Background: Although the vast majority of meningiomas are not malignant, their location within the cranial vault often leads to the development of symptoms. Traditional therapy has included observation, surgical resection, radiation therapy or a multimodality approach. The objective of this study is to review the outcomes in patients with meningioma treated at our institution using stereotactic radiosurgery.
Materials and Methods: A total of 73 patients (median age of 59, 15 male and 58 female) with meningioma (median volume of 5.54 cc) underwent Cyber Knife ^TM stereotactic radiosurgery at our institution. Sixty patients had WHO grade 1 meningioma, eleven patients had WHO grade 2 meningioma, and two patients had WHO grade 3 meningioma. Treatment consisted of a median dose of 17.5 Gy (range, 6 - 27 Gy) delivered over a median of three fractions (range: 1 - 5). The patients were followed by clinical examination as well as serial imaging with magnetic resonance imaging (MRI).
Results: The median follow-up was 16.1 months (range, 1.5 - 98.0). Follow-up MRI was available in all 73 patients. Local failure was documented in 11 cases. Actuarial local control at one year was 95, 71, and 0% for WHO grade 1, WHO grade 2, and WHO grade 3, respectively. There was no acute grade 3 or greater toxicity and only one episode of late grade 3 toxicity. A subjective improvement in the existing, tumor-related symptoms was noted in 60% of the patients.
Conclusion: Stereotactic radiosurgery is a safe and effective treatment for meningioma. Tumor-related symptoms often improve after treatment.