S5542 A Rare Case of Hepatocellular Carcinoma With Isolated Right Atrial Metastasis

Introduction: Hepatocellular carcinoma (HCC) metastasis to the right atrium is a rare finding occurring in 2.7%-4.1% of cases. Since HCC metastasizes hematogenously, tumor thrombus initially forms in the inferior vena cava (IVC) prior to the formation of an intracardiac mass; therefore, isolated cardiac metastasis is extremely rare. We present a case of isolated cardiac metastasis of HCC without tumor thrombus present in the inferior vena cava. Case Description/Methods: A 58-year-old woman with history of liver lesions and hypertension presented to the hospital with acute onset of abdominal pain, nausea, and vomiting. Vitals were stable on presentation and physical exam was pertinent for right upper and lower quadrant tenderness. Laboratory tests showed elevated aspartate transaminase 339 IU/L, alanine transaminase 126 IU/L, alkaline phosphatase 388, total bilirubin: 3.7, and alpha-fetoprotein level exceeded 200,000. Computed tomography (CT) and magnetic resonance imaging of the abdomen and pelvis showed multiple liver lesions with central scar, the largest lesion was located in the left lobe of the liver measuring 15.2 × 10 cm. During hospitalization, the patient reported experiencing intermittent chest pain prompting cardiac work up to include transthoracic echocardiogram (TTE). TTE revealed a 6 × 4 cm right atrial mass, other imaging showed no evidence of tumor thrombus present in the inferior vena cava. Cardiothoracic surgery was consulted and the decision was made to proceed with surgical removal of the right atrial mass. Intraoperative transesophageal echocardiogram confirmed the presence of a large right atrial mass between the tricuspid valve and the interatrial septum. The mass was successfully resected and tissue analysis was consistent with HCC. Ultimately, the etiology of the HCC found in this particular patient remains unknown. On post op day 2, the patient developed cardiogenic shock with multiorgan failure requiring pressure support, continuous renal replacement, and intubation. Despite critical care management, the patient went into cardiac arrest and expired on post op day 5. Discussion: There are no guidelines for the management of HCC with isolated cardiac metastasis. Since intravascular invasion occurs in the late stages of HCC, the prognosis of right atrial metastasis is poor and therapy is limited to systemic chemotherapy and radiation. It may be beneficial to approach treatment options with management of the underlying liver disease and consider chemotherapy, radiation, surgical resection, or palliative care on an individual basis.