Gamma knife radiosurgery for recurrent and residual meningeal hemangiopericytomas.
OBJECTIVE
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%.


CONCLUSIONS
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.
Sun
Shibin
S
Gamma Knife Center, Beijing Neurosurgical Institute, Tiantan Hospital, Capital University of Medical Sciences, Beijing, China. ssbwyl@vip.sina.com
Liu
Ali
A
Wang
Chongcheng
C
D000293:Adolescent; D000328:Adult; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008577:Meningeal Neoplasms / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery*; D008579:Meningioma / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology / Q000601:surgery*; D018365:Neoplasm, Residual / Q000473:pathology / Q000601:surgery*; D016634:Radiosurgery; D015996:Survival Rate; D055815:Young Adult