Predicting the Risk of New Cerebral Lesions After Stereotactic Radiosurgery (SRS) for Brain Metastases from Breast Cancer.

ABSTRACT

AIM: To generate a tool that estimates the probability of developing new cerebral metastases after stereotactic radiosurgery (SRS) in breast cancer patients. PATIENTS AND METHODS: SRS dose plus seven characteristics (age, performance score, number of cerebral metastases, maximum diameter of all metastases, location of metastases, extra-cerebral spread and time from breast cancer diagnosis until SRS) were analyzed regarding their ability to predict the probability of new cerebral metastases development following SRS. For those characteristics deemed significant, points of 0 (higher risk of new lesions) or 1 (lower risk) were given. Scores were generated by adding the points of significant characteristics. RESULTS: Performance score (p=0.013) and maximum diameter of all metastases (p=0.022) were associated with development of subsequent brain metastases. Two groups were created, 0-1 and 2 points. Freedom from new cerebral metastases rates were 27% and 92%, respectively, at 15 months (p=0.003). CONCLUSION: This tool helps select breast cancer with few cerebral metastases receiving SRS who may benefit from additional whole-brain irradiation.