Skull base meningiomas: Long-term results and patient self-reported outcome in 507 patients treated with fractionated stereotactic radiotherapy (FSRT) or intensity modulated radiotherapy (IMRT)

Abstract

Purpose: To evaluate long-term outcome of high-precision photon radiotherapy in 507 patients with skull base meningiomas.

Methods and materials: At the time of radiation therapy, most patients presented with clinical symptoms including double vision, headache, nausea, trigeminal or facial nerve dysfunction or exophthalmus. In general tumors extended into several regions of the skull base. In 54%, prior neurosurgical intervention was performed, which was a partial resection or biopsy in 266 patients. Treatment was delivered using a 6 MV linear accelerator or the tomotherapy system. Fractionated stereotactic radiotherapy (FSRT) was applied in 376 patients (74%) and intensity modulated radiotherapy (IMRT) in 131 patients (26%). A median total dose of 57.6 Gy (range 25-68 Gy) was prescribed in median (range 1.6-5 Gy). To evaluate long-term toxicity as well as quality of life (QOL), we sent out a detailed questionnaire put together with special questions regarding the skull base location of the tumors. Special focus was long-term sequelae including visual deficits, cranial nerve deficits, headaches, fatigue or any other symptoms impairing overall QOL. The median follow-up time was 107 months (range 1-270 months).

Results: Overall treatment was well tolerated. Local control for the whole cohort was 95% at 5 years and 88% at 10 years. Patients with benign histology had significant higher local control than high-grade meningiomas. For benign meningiomas, local control was 91% at 10 years. For high-risk meningiomas, local control was 81% at 5 years and 53% at 10 years. QOL was unchanged in 47.7% of the patients, and 37.5% showed improvement. Most patients reported an improvement of symptoms or steady state; in only few patients disorders worsened over time or side effects developed.

Conclusion: Precision photon radiotherapy leads to long-term tumor control with minimal side effects, but also with preservation of QOL in patients with skull base meningiomas.