Intravascular tumor extension in the inferior vena cava (IVC) is known to occur with abdominal tumors, such as renal cell, hepatocellular, adrenal cell carcinoma, and Wilm's tumor. We encountered a 53‐year‐old male patient presenting with pulmonary embolism and a right atrial mass with imaging evidence of an adrenal tumor extending into the IVC, up to the right atrium. The patient underwent surgery for the resection of the tumor using cardiopulmonary bypass by a team of cardiothoracic surgeons and urologists. Histology identified the tumor as hepatocellular carcinoma, which developed as ectopic hepatic tissue in the right adrenal gland.