gms | German Medical Science

Objective: Intracranial hemangiopericytoma is a rare CNS tumor that exhibits a high incidence of localrecurrence and distant metastasis. The purpose of this study was to evaluate the role of Gamma Knife Radiosurgery (GKRS) in themanagement of intracranial hemangiopericytomas.

Methods: From 15 participating centers under the auspices of the european gamma knife Society weperformed a retrospective observational analysis of a cohort of 115 hemangiopericytomas treatedwith GKRS. All were treated with Gamma Knife radiosurgery at least 5 years before assessment for this study. Clinical and imaging data were retrieved from each center and uniformly entered into a database by1 author (A.S.). A statistical analysis is presented.

Results: 77 patients harbouring 115 hemangiopericytomas treated in fifteen institutions recruited wereevaluated. The median age was 47 years (range 16-77 years). The median tumour volume was 3.30 ccm (range 0.1-20,4 ccm) and tumour margin dose to the 50% isodose line 15.0 Gy (range 10-40 Gy). The median radiological Follow Up was 47 months, but detailed results were only available for 92hemangiopericytomas (80%). The volume of treated tumours decreased in 22 lesions (24%) did notchange in 29 lesions (32%) and increased in 41 lesions (45%). The temporary morbidity rate after GKRS was 2.1% and the permanent morbidity rate was 2.6%. The actuarial control rate was 66% at 5 years post GKRS. A main limitation is the retrospective nature of data retrieval.

Conclusion: GKRS is a safe and not invasive method of treatment of hemangiopericytomas. The large number analyzed confirms a high tumour control and low morbidity rate even after a longterm follow up period.