Radiation therapy has multiple roles in the treatment of meningioma although surgery remains the primary treatment of choice. In this retrospective study, we report the results of radiation therapy for meningioma as definitive, postoperative or salvage therapies.
Methods
Seventeen patients diagnosed with meningioma were treated with radiation therapy in our institute from May 2000 to October 2009. Radiation therapies were performed as definitive therapies in 8 patients, as postoperative therapies in 5 and as salvage therapies in 4. Nine patients received stereotactic radiosurgery (SRS), 2 patients fractionated stereotactic radiotherapy (FSRT), and 5 patients 3-dimensional conformal radiotherapy (3DCRT). Radiation dose were 12 to 20 Gy for SRS, 36 Gy in 9 fractions for FSRT and 50.4 Gy in 28 fractions for 3DCRT. Follow-up imaging study of computed tomography or magnetic resonance imaging was performed at 6 to 12 months intervals and neurologic exam was performed with an interval less than 6 months.
Results
The median follow-up duration was 38 months (range, 12 to 85 months). Tumor progression after radiation therapy developed in one patient. The reduction of tumor volume measured on follow-up images were more than 20% in 4 patients and minimal change of tumor volume less than 20% were observed in 12 patients. Peritumoral edema developed in 4 patients and disappeared without any treatment. One patient had radiation necrosis.
Conclusion
Our experience is consistent with the current understanding that radiotherapy is as an effective and safe treatment modality for meningiomas when the tumor cannot be resected completely or when recurred after surgery.