Linac stereotactic radiosurgery: An effective and safe treatment for elderly patients with brain metastases

Abstract

To evaluate the outcomes of radiosurgery for brain metastases in patients 65 years or older. Between January 1994 and January 2003, 117 patients (47 women, 70 men), median age 71 years (range, 65-86 years), received radiosurgery for 227 metastases. Sixty-one patients (55%) presented symptoms in relation to the brain metastases. Thirty-eight patients (32%) received whole-brain radiotherapy. Median metastasis diameter and volume were 21 mm (range, 0.5-75 mm) and 1.7 cc (range, 0.02-71 cc), respectively. Median follow-up was 7 months (range, 1-45 months), 9.5 months for alive patients (range, 1-45 months). Median minimum and maximum doses were 14.5 Gy (6.5 Gy, 19.5 Gy), and 20.4 Gy (13.2 Gy, 41.9 Gy), respectively. Median survival was 8 months from the date of radiosurgery. Overall survival rates at 6 and 24 months were 58% +/- 5% and 13% +/- 4%, respectively. According to multivariate analysis, a low Karnofsky performance status was an independent unfavorable prognostic factor for overall survival (p = 0.003; odds ratio [OR] = 0.28; 95% confidence interval [CI], 0.14-0.56). Median brain disease-free survival was 10 months. Brain disease-free survival rates at 6 and 24 months were 67% +/- 6% and 40% +/- 7%, respectively. According to multivariate analysis, a radiosensitive lesion was an independent favorable factor (p = 0.038; OR = 0.42; 95% CI, 0.18-0.95); more than two metastases and a low Karnofsky performance status were independent unfavorable factors for brain disease-free survival (p = 0.046; OR = 2.15; 95% CI, 1.01-4.58 and p = 0.003; OR = 30.4; 95% CI, 3.1-296, respectively). Local control rates were 98% +/- 2% and 91% +/- 8.5% at 6 and 24 months. Out of the 61 patients presenting symptoms before radiosurgery, complete symptomatic response was achieved in 12 patients (20%), partial improvement in 25 (41%), stabilization in 7 (11%), and worsening in 4 (6%) related to a progression of the irradiated metastasis. Seven cases of radionecrosis were described and were related to the margin dose (p = 0.03). Radiosurgery for elderly patients was effective and safe. Age alone should not be a criterion for denying radiosurgery to any patient with brain metastases.