Background: Involvement of the inferior vena cava and right atrium by renal cell carcinoma is not uncommon, also paradoxical embolization resulting in a stroke has been reported. A discreet metastasis in the right atrium from renal cell carcinoma is much rarer and paradoxical embolization with growth of the embolus as discrete metastasis in the brain ultimately leading to the patients demise to our knowledge has never been reported.
Case Report: We report the case of a 54-year-old man with a history of bilateral renal cell carcinoma status post right radical and left partial nephrectomy who was admitted for evaluation of acute onset of confusion and dysarthria. Computer tomographic (CT) scan and magnetic resonance imaging (MRI) of the brain showed multiple areas of small infarcts. A transesopahgeal echocardiogram (TEE) demonstrated a 1.8 by 2.6 cm mass extending from the inferior vena cava (IVC) junction into the right atrium, as well as a large patent foramen ovale. Subsequent excision and histological examination of the mass confirmed presence of renal cell carcinoma metastasis to the heart. The small emboli to the brain eventually started growing confirming the suspicion that they were metastasis originating from the heart leading to the patients demise.
Conclusions: Renal cell carcinoma can form metastasis anywhere along the venous drainage from the kidneys. The metastasis do not have to be direct tumor extensions. In the presence of a right to left shunt further tumor embolization particularly to the brain is possible.

Keywords: Embolism, Carcinoma, Renal Cell, paradoxical, Stroke