Brain metastases in patients treated with targeted therapy for metastatic renal cell carcinoma (mRCC).

Abstract

326 Background: Patients with brain metastases from advanced RCC treated in the targeted therapy era are not well characterized. Methods: Data from patients with mRCC treated with targeted therapy were collected through the International mRCC Database Consortium from 6 centers. Results: One hundred six out of 705 (15%) patients with mRCC had brain metastases. Forty-seven patients had brain metastases at the start of first-line anti-VEGF therapy and the rest developed metastases during follow-up. Of the patients with brain metastases, 6%, 68%, and 26% were in the favorable, intermediate and poor prognosis groups, respectively, per the Heng et al JCO 2009 criteria. Ninety percent had cerebral metastases, 17% had cerebellar metastases, 40% had a Karnofsky performance status (KPS) <80%, and 81% had symptoms of brain metastases. The median largest size and number of brain metastases was 1.8 cm (range 0.2–6.6) and 1 (range 1–20), respectively. Patients were treated with first-line sunitinib (n=77), sorafenib (n=23), bevacizumab (n=5), and temsirolimus (n=1). Local disease treatment included whole brain radiotherapy (81%), stereotactic radiosurgery (25%), and neurosurgery (25%). The brain metastases of 59 patients were evaluable and based on the local treatment and/or targeted therapy achieved 7 (12%) complete responses, 23 (39%) partial responses, 14 (24%) patients with stable disease, and 15 (25%) patients with progressive disease in the brain metastases. Patients with more than 4 brain metastases vs. those with no more than 4 have an overall survival time from diagnosis of brain metastasis of 3.9 vs. 15.4 months (p=0.0051). Previous nephrectomy, sarcomatoid, and non-clear cell histology are not associated with development of brain metastases. On multivariable analysis, KPS<80% (p=0.0139), diagnosis to treatment with targeted therapy <1 year (p=0.0012), and higher number of brain metastases (p=0.0311) were associated with worse survival from diagnosis of brain metastases. Conclusions: In patients with brain metastases from RCC, KPS at start of therapy, diagnosis to treatment time and number of brain metastases may be prognostic factors for overall survival. [Table: see text]