Role of Gamma Knife surgery in patients with 5 or more brain metastases

Abstract

Object The authors evaluated overall survival and factors predicting outcome in patients with ≥ 5 brain metastases who were treated with Gamma Knife surgery (GKS). Methods Medical records from patients with ≥ 5 brain metastases treated with GKS between 1997 and 2010 at the Cleveland Clinic Gamma Knife Center were retrospectively reviewed. Patient demographics, tumor characteristics, treatment-related factors, and outcome data were evaluated. Results One hundred seventy patients were identified, with a median age of 58 years. The female/male ratio was 1.2:1. Gamma Knife surgery was used as an upfront treatment in 35% of patients and as salvage treatment in 65% of patients with multiple brain metastases. The median overall survival after GKS was 6.7 months (95% CI 5.5–8.1). At the time of GKS, 128 patients (75%) had concurrent extracranial metastases, and in 69 patients (41%) multiple extracranial sites were involved. Ninety-two patients (54%) had a history of whole-brain radiation therapy, and 158 patients (93%) had a Karnofsky Performance Scale (KPS) score ≥ 70. The median total intracranial disease volume was 3.2 cm3 (range 0.2–37.2 cm3). A total intracranial tumor volume ≥ 10 cm3 was observed in 32 patients (19%). Lower KPS score at the time of treatment (p < 0.0001), patient age > 60 years (p = 0.004), multiple extracranial metastases (p = 0.0001), and greater intracranial burden of disease (p = 0.03) were prognostic factors for poor outcome in the univariate and multivariate analyses. Conclusions In this study, GKS was safe and effective for upfront and salvage treatment in patients with ≥ 5 brain metastases. Gamma Knife surgery should be considered as an additional treatment modality for these patients, especially in the subset of patients with favorable prognostic factors.

Brain metastasis and treatment

“…Interestingly, the number of brain metastases was not a significant predictor of survival, but this may have been due to the relatively small size of the study. Higher intracranial burden (higher volume of brain metastases within the brain) predicted poorer outcomes [ 41 ]. The Japanese Leksell Gamma Knife Society conducted a study for one to 10 brain metastases and showed no difference in OS whether patients had two to four versus five or more brain metastases when treated with SRS alone [ 42 ].…”

Adaptive hypofractionated gamma knife radiosurgery in the acute management of large thymic carcinoma brain metastases

“…Based on our institutional experience and previous reports,[1826] we believe the tumor's histopathology/underlying radiosensitivity and RPA-surrogate factors might play a determinant role on RRR-outcome. In this particular patient case, the procedure proved highly successful by promptly ablating M3 and M4, hence avoiding further neurological impairment including aphasia, sensorimotor deficit, and epileptic activity.…”

The Expanding Role of Radiosurgery for Brain Metastases

“…A number of retrospective series have also reported outcomes of patients treated with SRS for ≥4 brain metastases with OS data presented in Table 1 for selected series. Notably, all of these series contain a proportion of patients treated with SRS for multiple metastases who had already received WBRT [ 39 , 40 , 41 , 42 ]. It is currently unknown whether the use of SRS upfront versus post WBRT differs in outcome.…”