gms | German Medical Science

Objective: The role of Gamma Knife radiosurgery for benign meningiomas has been well established. However the differences between the management of convexity(CM) vs. skull-base meningiomas(SBM) has not yet been analysed in detail and requires further long-term results. This study involves the experience of several European Gamma Knife Centres. We report on the efficacy of GKRS for the treatment of meningiomas, in respect to clinical and radiological control and side effects.

Methods: This is a retrospectivel report that reviews the material drawn from a cohort of over 5000 benign meningiomas treated with GKRS. A visit of the centres recruited was performed by the first author. A descriptive comparative analysis is presented.

Results: 4565 patients harbouring 5300 meningiomas treated in fifteen institutions recruited were evaluated. 3753 tumours were located in skull base, while 1547 were falx/convexity meningiomas. For SBM median age, tumour volume and median tumour margin dose to the 50% isodose line were 56.4 years, 5.2 ccm and 13.5 Gy respectively, for CM 59 years, 4.0 ccm and 14.0 Gy respectively. The median imaging follow-up was 61 months for SBM 59 months for CM. The control rate was 93.8% for SBM and 89.5% for CM. The permanent morbidity rate after GKRS was 5.6% for SBM and 5.4% for CM. The actuarial control rate was 97.9% and 94.1% at 5 years post GKRS respectively.

Conclusions: GKRS is a safe and non-nvasive method of treatment for meningiomas, although the large number analysed confirms a better tumour control for skull base tumours despite tumour dimensions comparable morbidity rate even after a long-term follow-up period.