Stereotactic radiosurgery as a salvage treatment option for atypical meningiomas previously submitted to surgical resection.

ABSTRACT

BACKGROUND: Surgery is the initial treatment for atypical meningiomas (AM), but in cases of recurrence, options become more limited. We present our results from salvage treatment with stereotactic radiosurgery (SRS) in previously surgically treated patients. METHODS: Sixteen patients treated between 1993 and 2007 were retrospectively reviewed. The mean follow-up was of 66.5 months. Most of the patients (81.3%) presented a single tumor nodule, while 3 presented multicentric disease (18.7%). Lesion volumes varied from 0.8 to 12 cm3 (mean 6.1 cm3). A dose of 12 to 16 Gy was prescribed according to isodose curves from 50 to 90%. RESULTS: After SRS, 3 of the patients (18.8%) presented with tumor volume reduction, 7 (43.8%) remained stable, and 6 patients presented with tumor progression. The Kaplan-Maier-estimated progression-free survival (PFS) and overall survival (OS) were 70.3% and 87.1% at 5 years and 44% and 54.4% at 10 years. Age, sex, site and tumor volume were not significantly associated with the prognosis. Patients presenting with multicentric disease presented a poorer prognosis, although without statistical significance (p = 0.14). CONCLUSIONS: SRS provided an effective and safe treatment for this group of patients with recurrent NBM. Patients who present with multicentric disease will probably fare more poorly.