CyberKnife Stereotactic Radiosurgery in brain metastases: A report from Latin America with literature review.

Background and aim: Stereotactic radiosurgery is increasingly being employed for the treatment of brain metastases, both as an adjuvant to surgical resection, and also as a primary treatment modality. The aim of this study is to evaluate overall survival and local control in patients with brain metastases treated with CyberKnife Stereotactic Radiosurgery (CKRS), due to the lack of evidence reported in Latin America.

Materials and methods: We performed a retrospective chart review from October 2011 to January 2017 of 49 patients with 152 brain metastases. Clinical and prognostic factors were further analyzed by independent analysis. Kaplan-Meier curves were constructed for overall survival and local control. The median follow-up period was 12 months (range, 1-37 months).

Results: The median age was 61 years (range, 27-85 years) and Karnofsky performance status >70 in 96% of the patients. The median overall survival rate was 15.5 months (95% confidence interval [CI], 10.23-24.3 months). Overall 3-month, 6-month and 1-year local control rates were 98% (95% CI, 85-99%), 96% (95% CI, 82-99%), and 90% (94% IC, 76-96%), respectively. Local failure (LF) was observed in 6 patients (18 lesions). No late complications, such as radiation necrosis, were observed during the follow-up period.

Conclusions: CKRS achieves excellent overall survival and local control rates with low toxicity in patients with brain metastases.