BM-20EVALUATION OF RISK FACTORS FOR DEATH WITHIN THREE MONTHS AFTER STEREOTACTIC RADIOSURGERY FOR BRAIN METASTASES

摘要

BACKGROUND: Stereotactic radiosurgery (SRS) is used commonly for patients with brain metastases (BM) to improve intracranial disease control. However, survival of these patients is most often dictated by the course of their systemic disease, and use of SRS for all patients with BMs is not an appropriate use of limited medical resources. We evaluated prognostic factors which may predict early death (within 90 days) after SRS. METHODS: 1427 patients with BM were treated with SRS at our institution (2000-2012) and their data are maintained in an IRB approved database. 1395 cases were included in this study. The primary end point of the study was mortality within 90 days after first SRS. Multivariate analysis was performed and a predictive model was developed to determine a prognostic index for 90-day mortality. RESULTS: Overall, 53% of patients were female, median age at diagnosis of the primary cancer was 58 years. Multiple BM was observed in 773 patients (55%), 108 patients (8%) had KPS 60 or lower at time of SRS and 1069 patients (77%) had other extra-cranial metastases. 263 patients (19%) died within 90 days after SRS. Multivariate analysis showed that KPS (p < 0.0001), extracranial metastases at SRS (p < 0.0001), number and size of BM (p = 0.003), and prior surgery (p = 0.001) were independent prognostic factors for 90-day mortality. We developed a prognostic model by assigning a weighted score to each significant factor from the multivariate analysis that is proportional to its hazard ratio. The total score for each patient was determined by summation, and four independent prognostic groups could be determined from the total scores. We found that the lowest scoring group had a 44% chance of early mortality versus 4% in highest scoring group (P < 0.0001). CONCLUSIONS: Prospective validation of this 90-day mortality risk prognostic model may provide a valuable tool for appropriate clinical resource utilization.