Brain metastases (BMs) from metastatic renal cell carcinoma (RCC) in patients (pts) treated with molecularly targeted agents (MTAs).

Abstract

e15066 Background: Historically, the frequency of BMs from RCC is ~11%. Recent reports have suggested an improvement in the incidence of BMs with tyrosine kinase inhibitors (TKIs). What is not known is the impact of MTAs on the prevalence of BMs in metastatic RCC. Methods: We conducted a retrospective review of all pts with metastatic RCC treated with MTAs at a tertiary care center, UT Southwestern Harold C. Simmons Comprehensive Cancer Center, from 2006–2010. Statistical analyses were performed using the Cox proportional hazards model and the Kaplan-Meier method. Results: Fifty nine pts met inclusion criteria. 8 more pts presented with BMs and were not included in the incidence and survival analyses. Median age was 64.6 yrs. Per MSKCC criteria, 3 pts were in favorable (5%), 41 in intermediate (70%), and 15 in poor (25%) prognostic groups. Sites of metastases at presentation included lungs (65%), lymph nodes (40%), bones (30%), and liver (25.4%). Mean follow up time was 16 months, and at last follow up 24 pts were alive. The incidence of BMs was 11.9% (7/59) and the prevalence was 22% (15/67). Median overall survival was 1.97 yrs (95% CI, 1.04-3.89). Median survival for pts who developed BMs vs. without BMs was 1.21 yrs vs. 1.98 yrs (p=0.17). In multivariable analyses, only lack of nephrectomy was associated with increased risk of BMs, HR=9.819 (95 CI, 1.65-58.38; p=0.012). Conclusions: In our study, the incidence of BMs in RCC pts treated with MTAs was similar to what has been historically reported. In contrast, the prevalence of BMs was much higher at 22%. This is the first study to report the prevalence of BMs in patients with metastatic RCC treated with MTAs. As in other tumor types, the life-time risk of BMs appears to increase with the availability of highly-active MTAs.