Background

Brain metastases (BMs) in renal cell carcinoma (RCC) have historically been associated with a poorer prognosis. BMs are also usually asymptomatic, leading to a poor pick-up rate. While the incidence of BMs in RCC patients has slowly increased over the past decade, not much is known about its natural course or the optimum treatment pathway for as most of these patients are excluded from clinical trials. This study details the experience of a tertiary centre over the last 10 years in managing this condition.

Method

A retrospective study of 10-year data on RCC patients with BMs were performed across four West Midland teaching hospitals.  The data collected included demographics, time to relapse of brain metastases with or without progressive primary disease, subsequent local and systemic treatments, and performance status. Overall survival (OS) of patients receiving different treatment modalities was analysed and presented on Keplan-Meier curves.

Results

22/40 patients (55%) presented with metastatic disease. None of the female patients had BMs on presentation; 9 (31%) male patients did (p=0.043).

The median OS (95%CI) was 9 months (1-35) in those with BMs at presentation and 35 months (21-68) in those with distant metastases but no BMs (p=0.0509). Median OS (95%CI) from time of first occurrence of BMs was 9 (1-35) months in those who had BMs at presentation and 35 (21-44) months if developed later (p=0.0401).

Median time to relapse in both those who presented with metastatic disease and who did not present with metastatic disease was 15 months (95%CI: 4-75, 9-27 respectively).

A larger proportion of patients treated with SRS (versus surgery +/- radiotherapy or WBRT alone) were alive at the end of the surveillance period, but this was not statistically significant (p=0.2178).

Conclusion

BMs at presentation confers a worse prognosis versus a disease course where BMs develop later. However, metastatic disease at initial presentation may not be a risk factor for post-surgical relapse.

SRS alone showed a greater survival benefit than combination surgery and radiotherapy or WBRT alone, but this was not statistically significant.

Impact statement

SRS is potentially a superior treatment option for this condition, but a well-powered trial is needed to prove this.