A left atrial mass in a patient with atrial fibrillation and previous renal cancer.

A 73-year-old man underwent a surveillance CT following a laparoscopic radical nephrectomy for left-sided renal cell carcinoma 3 years earlier. He had atrial fibrillation. CT identified a large left atrial mass. The differential diagnosis of this mass was thrombus, primary cardiac tumour or cardiac metastasis secondary to his previous renal cell carcinoma. Location, size and appearance of the mass on echocardiogram were unusual for a left atrial thrombus; however, following surgical removal pathological examination confirmed this as an organised thrombus. A brief discussion on diagnostic evaluation of a left atrial mass follows the case report.