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Gamma Knife surgery in the treatment paradigm for foramen magnum meningiomas
Georgios Zenonos1, Douglas Kondziolka, John C Flickinger
1Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA. zenonosg@upmc.edu
Object:
Microsurgical management of foramen magnum meningiomas (FMMs) can be associated with significant morbidity and mortality. Stereotactic radiosurgery may be an efficient and safe alternative treatment modality for such tumors. The object of this study was to increase the documented experience with Gamma Knife surgery (GKS) for FMMs and to delineate its role in an overall management paradigm.
Methods:
The authors report on their experience with 24 patients harboring FMMs managed with GKS. Twelve patients had primary symptomatic tumors, 5 had asymptomatic but enlarging primary tumors, and 7 had recurrent or residual tumors after a prior surgery.
Results:
Follow-up clinical and imaging data were available in 21 patients at a median follow-up of 47 months (range 3-128 months). Ten patients had measurable tumor regression, which was defined as an overall volume reduction > 25%. Eleven patients had no further tumor growth. Two patients died as a result of advanced comorbidities before follow-up imaging. One patient was living 8 years after GKS but had no clinical evaluation. Ten of 17 symptomatic patients with at least 6 months of follow-up had symptom improvement, and 7 remained clinically stable. Smaller tumors were more likely to regress. No patient suffered an adverse radiation effect after radiosurgery.
Conclusions:
Gamma Knife surgery was a safe management strategy for small, minimally symptomatic, or growing FMMs as well as for residual tumors following conservative microsurgical removal.
Insights
Gamma Knife surgery (GKS) offers a safe and effective treatment for foramen magnum meningiomas (FMMs), showing tumor control and symptom improvement in most patients with minimal adverse effects.
Area of Science:
- Neurosurgery
- Radiation Oncology
- Oncology
Background:
- Foramen magnum meningiomas (FMMs) present significant surgical challenges.
- Microsurgical resection of FMMs is associated with high rates of morbidity and mortality.
- Stereotactic radiosurgery is emerging as a potentially safer alternative.
Purpose of the Study:
- To document the experience with Gamma Knife surgery (GKS) for FMMs.
- To evaluate the safety and efficacy of GKS in managing FMMs.
- To define the role of GKS within the FMM treatment paradigm.
Main Methods:
- Retrospective analysis of 24 patients with FMMs treated with GKS.
- Patients included primary symptomatic, asymptomatic but growing, and recurrent/residual tumors.
- Clinical and imaging data were collected for follow-up evaluation.
Main Results:
- Tumor control was achieved in all 21 evaluated patients (10 regression, 11 stable growth).
- Symptom improvement or stability was observed in 17 of 17 symptomatic patients.
- No adverse radiation effects were reported; smaller tumors showed higher regression rates.
Conclusions:
- Gamma Knife surgery is a safe and effective management option for FMMs.
- GKS is suitable for small, minimally symptomatic, or growing FMMs.
- GKS is also effective for residual tumors after surgical removal.
