RCC frequently presents with hemorrhagic BrMs. BrM distribution patterns and their associations with lab/clinical parameters are poorly understood.

A total of 67 BM were analyzed from 46 patients (age 63±10years/35M), 23 synchronous BM, 9 patients had two, 6 had 3 concurrent BrMs. 97% of the lesions were spheric in shape. Mean 1D and 2D (RANO) tumor dimensions were 2.0±1.1cm and 4.7±4.9cm², respectively and correlated with neutrophil count at BrM diagnosis (r=0.3, p=0.01). Multilobar edema was seen in 36% of BrM. 82% of BrMs contained hemosiderin and 80% were hemorrhagic. Most BrMs were in the frontal (45%), parietal (21%) and occipital (18%) lobes. Posterior cerebral artery distribution contained 34% of BrM despite it supplying only 16% of brain volume. Higher platelet counts were associated with BrMs in the posterior circulation territories (p=0.05). 

BrM hemosiderin was associated with larger tumors (p=0.04), lower platelet counts (p=0.01) and higher hemoglobin (p=0.08). Renal vein thrombosis (RVT) at primary diagnosis was associated both BrM hemosiderin (p=0.05) and hemorrhage (p=0.03). CNS progression-free survival was shorter in those who had RVT (p=0.04), or had BrM hemosiderin (p=0.04).