Fractionated stereotactic radiation therapy in the management of benign cavernous sinus meningiomas : long-term experience and review of the literature.

Purpose: To analyze own long-term results with fractionated stereotactic radiotherapy (FSRT) in patients with benign meningiomas of the cavernous sinus and to review the literature on these rare lesions.
Patients and Methods: 57 patients were treated with FSRT for benign meningiomas of the cavernous sinus between 01/1990 and 12/2003 at the authors' institution. Histology was WHO grade I in 28/57 lesions, and undetermined in 29/57 lesions. 29 patients received radiotherapy as primary treatment, ten following surgery, and 18 patients were irradiated for recurrent disease. Median target volume was 35.2 cm3. Median total dose was 57.6 Gy with 1.8 Gy per fraction. 51/57 patients showed clinical symptoms before radiotherapy like reduced vision (n = 19), diplopia (n = 25), or trigeminal hyp-/dysesthesia (n = 17).
Results: Median follow-up period was 6.5 years. 50/57 patients were followed for > 36 months. Overall local tumor control was 100%. 39/57 patients had stable disease based on CT/MRI, while 18/57 had a partial remission of tumor volume. Overall survival for patients with WHO grade I meningiomas was 95.5% after 5 and 10 years. Two patients died 2.8 and 4.1 years after radiotherapy due to cardiac failure. In 11/57 patients, preexisting neurologic deficits improved. There was one patient with recurrent hyperlacrimation of one eye on the side of the irradiated meningioma. Three patients complained about subjective visual deterioration after FSRT without any objective findings in an ophthalmologic examination. No late toxicity RTOG >/= degrees III was seen.
Conclusion: These data demonstrate that FSRT is an effective and safe treatment modality for local control of benign cavernous sinus meningiomas with a minimal risk of significant late toxicity.