Isolated Left Ventricular Metastasis from Renal Cell Carcinoma: Diagnostic and Therapeutic Dilemma

BACKGROUND: The treatment of metastatic renal cell carcinoma (RCC) has been radically changed by the advent of tyrosine kinase inhibitors (TKIs). However, few reports have described their role in cardiac metastases. We present a case of a left ventricular metastasis from RCC that was managed with pazopanib therapy. CASE REPORT: A 74-year-old male with stage I RCC underwent right nephrectomy in 2004 and right lung metastasis resection in 2009. He was well till March 2016, when he presented with chest pain. Cardiac catheterization revealed a highly vascular mass in the apex. Cardiac magnetic resonance imaging revealed a left ventricular mass with full-thickness involvement of the myocardium, and the open cardiac biopsy was consistent with metastatic RCC. The patient was initially treated with pazopanib with response but later developed therapy-related side effects, and the dose was reduced. Due to tumor progression, he is currently on nivolumab instead and is stable. CONCLUSION: RCC with cardiac metastasis poses unique challenges with regard to diagnosis as well as treatment. The use of TKI therapy is associated with cardiotoxicity and has not been adequately studied in cardiac metastasis. Choosing the right treatment for this subgroup of patients continues to pose an ongoing dilemma.