Metastatic renal cell carcinoma

Selected images of the brain demonstrating a right frontal lobe mass characterized by an spontaneous hyperdense rim with a vivid contrast enhancement and a central hypodense area (necrotic?). This lesion has a local mass effect with vasogenic edema and mild anterior mediline shift.     

Selected images of the abdomen showing an heterogeneous left kidney mass involving the lower pole and the hilum. There are associated mild hydronephrosis and venous congestion on the left gonadal vein. 

There is an irregular thick peripherally enhancing mass within the superior aspect of the middle frontal gyrus of the right frontal lobe with dimensions of 24mm (trans) x 29mm (AP) x 31mm (CC). Intrinsic T1 hyperintensity within this mass is present, which corresponds with signal dropout on EPI consistent with blood product. There is heterogeneous signal on T2 weighted imaging. Extensive edema is present within the right frontal lobe which effaces the cerebral sulci and has mass effect on the right lateral ventricle frontal horn. The falx cerebri is bowed slightly to the left. Midline shift to the left of 3mm measured at the septum pellucidum. No other abnormal enhancement is present. DWI & T2* perfusion are difficult to interpret in the setting of blood product within the right frontal mass, but there is peripheral increased CBV. Spectroscopy demonstrates a markedly elevated lipid/lactate peak within the non-enhancing center of the mass, consistent with necrosis. There is reduced NAA and reversed choline: creatine ratio. No hydrocephalus. No acute infarct.

Conclusion: Solitary hemorrhagic right frontal mass is most likely a metastasis in the context of previous renal cell carcinoma. A GBM is less likely.