Survival After Salvage Radiosurgery Is Significantly Affected By Status Of Systemic DiseaseKevin McMullen1, Sunit Harris1, James Lovato1, Thomas Ellis1, Stephen Tatter1, Edward Shaw1, Michael Chan11Wake Forest University Baptist Medical Center, Winston Salem, NC, USA Keywords: brain metastasis, gamma knife, cancer, radiosurgery, outcome
Salvage options for new or progressing brain metastases after whole brain irradiation include surgery, salvage radiosurgery (S-RS) and repeat whole brain irradiation (RWBI). Treatment decision making takes into account number of lesions, patient performance status, surgical resectability and status of systemic disease among other factors. With improved systemic chemotherapy, treatment failure in the central nervous system after WBRT is a more frequently occurring phenomenon. Factors predicting survival in this scenario to aid in decision making remain inadequately defined.
Radiosurgery in the salvage setting may lead to prolonged survival, however other disease related factors may mitigate any effect on survival.
Between November 1999 and June 2009, 259 patients underwent 333 RS procedures at Wake Forest University Baptist Medical Center for recurrent brain metastases after previous WBRT.
A retrospective analysis was performed using data obtained from patient charts and archived plans from the Leksell GammaPlan system. Patient-related factors including age, histology, and status of primary and extracranial metastatic disease, among others were recorded for analysis. Brain disease factors recorded included the time intervals between a) first brain metastases and failure after WBRT b) S-RS and recurrent brain metastases and c) S-RS and date of death.
Median survival of the entire cohort after S-RS was 7.3 months. Documented radiographic leptomeningeal failure was low (3.86%). Patients with 1) absent or non-visceral (bone) oligometastatic disease had longer survival than those with 2) visceral oligometastatic disease or widespread metastatic disease. Cox Proportional Hazards Regression Analysis revealed hazard ratios for overall survival for these two cohorts were 1.0-1.19 vs. 1.85-1.86 (p=0.008). Status of systemic disease at time of S-RS also predicted for survival. Hazard ratio for patients with progressing extracranial disease was significantly higher (1.79, p=0.0002) than those with absent/stable extracranial disease (1.0) at the time of S-RS.
This is a retrospective study.
S-RS offers patients a median overall survival of greater than 6 months in our series. In multivariate analysis, the overall burden and status of systemic disease at time of S-RS impacted survival.
Treatment decision making with regard to offering S-RS to patients should take into account the burden and status of systemic disease and the availability of active systemic therapy options to address their extracranial disease. Project Roles:
K. McMullen (), S. Harris (), J. Lovato (), T. Ellis (), S. Tatter (), E. Shaw (), M. Chan ()