Gamma knife radiosurgery for intracranial hemangioblastomas--outcome at 3 years

To define the role of Gamma Knife radiosurgery (GKRS) for the treatment of patients with hemangioblastomas.

Between 1992 and 2009, 26 hemangioblastomas in 14 patients (9 female and 5 male) were treated with GKRS. Mean age of patients at the time of treatment was 45.1 years (range 25-61). von Hippel-Lindau disease was established in 7 patients, and 7 patients had sporadic hemangioblastomas. Twenty-one tumors were solid, 4 were cystic, and 1 had both components. Four patients were treated with upfront radiosurgery, and 10 were treated following a resection. Mean tumor volume was 1.65 cm3 (range 0.08-9.02, median 1.1 cm3). Mean dose to the tumor margin was 18 Gy (range 10-25, median 18). Patients were assessed clinically and radiologically at 6- to 12-month intervals following GKRS. The median follow-up was 3 years (range 0.5-12 years). Kaplan-Meier analysis was used to assess factors predictive of tumor progression, and factors predictive in univariate analysis (P < 0.10) were entered into Cox multivariate regression analysis.

On follow-up, 4 tumors were stable in volume (15%), 14 decreased (54%), and 8 increased (31%). Local tumor control rates at 1, 5, and 10 years was 89%, 74%, and 50%, respectively. There was a trend toward tumor progression in sporadic patients (P = 0.10), women (P = 0.09), and larger tumors (P = 0.10). In patients with multiple hemangioblastomas as compared to those with only a solitary hemangioblastoma, the radiosurgically treated lesion was 7.9 times more likely to progress after GKRS treatment (P = 0.018). This remained the only significant predictor in multivarialble analysis. At the last clinical follow-up, seven patients showed no change or improvement in their symptoms and seven deteriorated.

Stereotactic radiosurgery offers a reasonable rate of tumor control and preservation of neurologic function in patients with hemangioblastomas. Patients with multiple hemangioblastomas are less likely to exhibit long-term tumor control of treated lesions following radiosurgery.