Results of radiotherapy for meningeomas with high risk for local recurrence. A retrospective analysis

Aim: Retrospective assessment of the efficacy of radiatiotherapy for meningeomas with high risk for local recurrence. Patients and methods: Records of 67 patients with meningeomas treated from 1974 to 1995 at 2 centres were analyzed. Follow-up time ranged from 0.8 to 213 months (median: 61 months). Radiation therapy was given either after local failure or after biopsy or subtotal resection. The ratio between malignant (n=20) and benign (n=47) meningenoma was 1:2.4. Median age of the patients was 55 years (7 to 77 years). Radiation treatment was given at 1.5 to 2 Gy per fraction to 36 to 79.5 Gy. Survival rates were calculated by the Kaplan-Meier method. Statistical comparisons were performed with the log-rank test and the Cox proportional hazards model. The Bonferroni method was used to correct for multiple comparisons. Results: Five- and 10-year disease-free survival rates were 82%±5% (standard error) and 70%±9%. Local control rates at 5 and 10 years were 78%±5% and 68%±9%. In uni- and multivariate analysis histology, sex, total dose and center showed no significant influence on the results. Patients age was significant for local control (univariate p=0.02; multivariate p=0.03) and disease-free survival (univariate/multivariate p=0.04). The postoperative tumor burden had a significant influence of disease-free survival (multivariate P=0.04). After Bonferroni correction no significant influence was observed. We did not observe late side effects, especially brain necrosis. Conclusions: Despite of the negative selection of our patients we observed high survival- and local control rates after radiation therapy. This underscores the role of radiation therapy in the treatment of meningeomas with high risk of local failure. (orig.)