Does Advanced Age Affect the Outcomes of Stereotactic Radiosurgery for Cerebral Arteriovenous Malformation?

BACKGROUND: Stereotactic radiosurgery (SRS) is generally considered a minimally invasive treatment modality. However, definitive evidence of the efficacy of SRS in the elderly population is still not available. METHODS: The outcomes of 561 elderly and nonelderly patients who underwent SRS for AVM at our institution between 1990 and 2013 were reviewed, analyzed, and compared. Elderly patients were defined as those age >= 60 years at the time of SRS. RESULTS: The elderly cohort comprised 55 patients; the nonelderly cohort, 506. In the elderly cohort, the median age was 65 years, and the duration of follow-up was 91 months. The actuarial obliteration rates were 47% at 3 years, 70% at 4 years, and 76% at 5 years in the elderly cohort, and 57% at 3 years, 76% at 4 years, and 83% at 5 years in the nonelderly cohort. In the elderly cohort, the hemorrhage rates during the post-SRS latent phase were 5.2%/year in patients with hemorrhagic onset and 0%/year in those with nonhemorrhagic onset, and event-free survival (EFS) was 93% at 6 years and 89% at 12 years. The obliteration rate, mortality, and EFS rate were not significantly different between the 2 cohorts, whereas the rate of perifocal edema was significantly lower (P = 0.021) in the elderly cohort. The pre-SRS and post-SRS hemorrhage rates were slightly higher in the elderly cohort, albeit without statistical significance. CONCLUSIONS: Therapeutic effects and outcomes of SRS are similar in elderly and nonelderly patients. Treatment-related neurologic deficits are rare, and longer EFS can be expected.