RESUMO
A primary right atrial (RA) mass is not common; instead, most tumors in the right atrium originate from metastasis through the caval route. Here we describe a patient with a huge RA tumor that showed contiguous spread from the inferior vena cava. This 60-year-old patient, positive for hepatitis B surface antigen, visited the emergency department of our institution due to recently aggravated dyspnea. Transthoracic and transesophageal echocardiography clearly demonstrated a huge RA mass, 6.5x6.0 cm, causing flow disturbance. Cardiac magnetic resonance imaging and dynamic computed tomography of the liver showed multiple large hepatic masses that extended into the right atrium, with tumor thrombi in the inferior vena cava. Given the enhancement pattern in dynamic computed tomography of the liver, the hepatic mass was diagnosed as hepatocellular carcinoma. Due to the risk of spontaneous rupture of the mass, emergency transarterial chemoembolization was performed, without complications. Thereafter, thalidomide, which has been shown to have anti-angiogenic effects, was prescribed to the patient.