Abstract
INTRODUCTION
The suitability of stereotactic radiosurgery (SRS) in patients with 5-15 brain metastases (BM) is being evaluated in the ongoing CCTG CE.7 randomized trial testing SRS against HA-WBRT. Our study examines the survival of patients with 5-15 BM treated at initial SRS.
METHODS
Review of our Gamma Knife registry identified 163 patients who fulfilled CCTG CE.7 eligibility criteria.
RESULTS
92 females (56%) and 71 males (44%) with median age of 51.6 years (23-98.9) and primary diagnoses of lung (n = 108, 28 EGFR/ALK mutations), breast (n =14, 1 Her2+), melanoma (n = 27, 9 BRAF+), and 14 other were identified. 145 had active extracranial disease (89%); median KPS was 90 (50-100). Median number of tumors at first SRS was 8.2; 114 patients (70%) had 5-9 and 49 (30%) had 10-15 tumors. 73 patients (45%) had subsequent SRS to a median of 19 (6-84) cumulative subsequent tumors at a median time to 2nd treatment of 3.9 months (0.7-30.3). 32 patients (20%) had a 3rd SRS and 24 patients (15%) had 4 or more treatments. 16 patients (10%) received WBRT after initial SRS. 73 patients (45%) were alive at time of data analysis. Median OS from initial SRS for all patients was 15.5 months and was 15, 17.6, 13.4, and 8.7 months, for breast, lung, melanoma, and other respectively. Median OS with 5-9 metastases vs 10-15 metastases was 17.5 vs. 13.3 months (p=.15). Median OS with vs without subsequent SRS was 21.8 vs 8 months (p=.0013).
CONCLUSION
Patients with 5-15 BM treated with initial SRS can achieve survivals that compare favorably with or better than those of WBRT. These findings potentially challenge the assumption that such patients may be better candidates for HA-WBRT than upfront SRS. Our experience supports the ongoing efforts to prospectively evaluate upfront SRS in these patients.