Asymptomatic Right Atrial Mass as Initial Manifestation of Non-Cirrhotic Hepatocellular Carcinoma

Abstract

Purpose: A 51-year-old male with past medical history of Down syndrome and chronic hepatitis B virus (HBV) infection was referred from the clinic for evaluation of the right atrial mass which was found incidentally on his routine examination. Patient denied dyspnea, orthopnea, chest pain, confusion, tremors, malaise or weakness. Physical examination revealed classic craniofacial dysmorphology of Down syndrome. There was no evidence of icterus, hepatosplenomegaly, abdominal tenderness or distension. An electrocardiogram showed normal sinus rhythm with normal axis and a chest radiography showed enlargement of the cardiac silhouette. CT scan showed large infiltrating tumor within the liver with venous invasion into the middle hepatic vein, inferior vena cava and right atrium. The biopsy of hepatic mass was not performed because the positive HBsAg, elevated AFP and a new hepatic lesion seen on CT scan obviate the need for biopsy to diagnose hepatocellular carcinoma (HCC). The major risk factor for HCC is cirrhosis and only 10 to 20% of cases of HCC develop without cirrhosis. The incidence of metastatic HCC to the right heart cavity is reported to be less than 6% in an autopsy series. This group of patients often exhibits symptoms of heart failure owing to flow obstruction or thromboembolism. This case has the distinction of comprising three rare entities: 1) non-cirrhotic HCC, 2) intracardiac metastases, and 3) lack of clinical manifestations.Figure 1: An infiltrating 102 × 95 mm mass within the right lobe of the liver.Figure 2: Atrial phase of CT scan shows a filling defect within the right atrium.