Aims: The aim of this study was to assess the clinical effects of Gamma Knife radiosurgery (GKS) for recurrent and residual meningeal hemangiopericytomas (M-HPC).
Methods: Between December 1994 and December 2006, 22 patients with recurrent and residual M-HPC with 58 foci underwent GKS at the Gamma Knife Center of Beijing Neurosurgical Institute. Of these 22 patients, 13 patients (59.1%) were males and 9 patients (40.9%) were females. The mean age was 40.9 years (range 16-64 years). The mean volume of these tumors was 5.4 cm(3) (range 0.1-37.2 cm(3)). The mean tumor margin dose was 13.5 Gy (range 10.0-20.0 Gy). The mean tumor central dose was 28.2 Gy (range 21.8-35.0 Gy). The mean prescription isodose line was 48.4% (range 30.0-70.0%).
Results: The mean period of follow-up was 26.0 months (range 5-90 months). Of these 22 patients, intracranial metastases developed in 7 patients (31.8%), extracranial metastases developed in 3 patients (13.6%). Four patients died. The mean life expectancy of these 22 patients was 67.7 months (range 7-192 months). Of these 58 foci, radiological follow-up showed that 25 foci (43.1%) nearly disappeared, 13 foci (22.4%) shrunk, 14 foci (24.1%) remained stable and 6 foci (10.3%) enlarged. The overall tumor control rate was 89.7%.
Conclusion: GKS provides an effective and safe adjunct management for postoperative small-to-moderate sized M-HPC and plays an important role in controlling recurrent and residual M-HPC to avoid a repeat surgical resection.
(c) 2009 S. Karger AG, Basel.