Rare Case of Intracardiac Renal Cell Carcinoma Metastasis with Response to Nivolumab: Case Report and Literature Review

Intracardiac metastases in the absence of inferior vena cava involvement is a rare occurrence in patients with metastatic renal cell carcinoma (mRCC). There is limited evidence regarding the efficacy and safety of standard treatment modalities for mRCC patients with intracardiac metastases. Presence of intracardiac metastases is known to indicate poor prognosis and may potentially increase risk of treatment-related complications. Recent advances in RCC management have integrated nivolumab, a programmed death-1 (PD-1) receptor inhibitor, as a preferred treatment option in the second-line setting after failure of prior anti-angiogenic therapy; or in combination with ipilimumab, an anti-Cytotoxic T-lymphocyte antigen-4 antibody as first-line therapy for intermediate to poor risk patients with mRCC. The efficacy and toxicity of nivolumab in patients with mRCC and intracardiac metastases has never been reported previously. We herein present the first reported case of mRCC with intracardiac metastasis and a resultant excellent response to nivolumab treatment and discuss the imaging techniques and treatment options for this rare presentation.