A Simple and Practical Scoring System for Radiosurgical Treatment in Patients with Brain Metastases.

BACKGROUND: The study aimed to investigate the prognostic factors for patients with brain metastases undergoing radiosurgical treatment and to introduce a simple and practical scoring system for the prediction of survival time. METHODS: We retrospectively analyzed data for 311 patients treated with Gamma Knife radiosurgery at a single institute. The mean age at time of treatment was 60 years (range 23-86 years), and the median Karnofsky performance status (KPS) score was 90 (range 60-100). Using a new prognostic index, the prognostic index for brain metastases (PIBM), the patients were categorized into 3 groups according to the primary tumor status and KPS score. We performed survival analysis and compared the prognostic ability of the PIBM with other published indices. RESULTS: During the median follow-up duration of 8.2 months (range 0.1-109 months), the median overall survival time was 9.1 months. Stable primary tumor status (hazard ratio [HR] 0.497, 95% confidence interval [CI] 0.321-0.769, p = 0.002) and KPS score ≥90 (HR 1.407, 95% CI 1.018-1.946, p = 0.039) significantly predicted longer overall survival. The PIBM showed the lowest Akaike information criterion value and the highest integrated area under the curve value compared with other prognostic indices. CONCLUSIONS: The PIBM may be a more accurate prognostic indicator than other published indices. Although this new and practical prognostic index requires further validation in larger cohort studies, we suggest that the PIBM could be useful to predict survival time and inform appropriate management of patients with brain metastases.

Identifying candidates for gamma knife radiosurgery among elderly patients with brain metastases.

We investigated the outcomes of gamma knife radiosurgery (GKRS) for elderly patients (≥ 65 years) with brain metastases, and identified survival-associated factors. We retrospectively analyzed data from 115 patients treated with GKRS for 1-15 brain metastases. The median patient age was 72 years; most primary tumors were pulmonary (n = 83). The mean lesion volume was 2.1 ± 4.8 mL. A mean dose of 19.3 Gy was delivered to the mean 63.9% isodose line. The median overall survival (OS) was 5.3 months (95% confidence interval [CI] 3.5-7.1). During follow-up (median, 5.1 months), 91 patients died of primary cancer progression while 1 died of unknown causes. The 6- and 12-month local control rates were 94.9 and 88.1%, respectively. On multivariate analysis, female sex (p = 0.005, hazard ratio [HR] 0.533, 95% CI 0.343-0.827) and a controlled primary tumor (p < 0.001, HR 0.328, 95% CI 0.180-0.596) were significantly favorable prognostic factors. Of non-small cell lung cancer patients with EGFR mutations, 76.5% were women (p = 0.005). The median OS of EGFR-mutant and EGFR-wildtype patients were 19.1 and 4.7 months, respectively (p = 0.080). Brain metastases < 3 mL showed better local control rates after GKRS (p = 0.005). GKRS produces favorable outcomes in women with brain metastases who are ≥ 65 years and have controlled primary tumors. Such patients are therefore suitable candidates for GKRS.