Isolated Metastasis of Hepatocellular Carcinoma in the Right Ventricle

Abstract

A74-year-old man was admitted to our hospital for liver tumor found through magnetic resonance imaging (MRI). An electrocardiogram (EKG) revealed a negative T wave at V1-V4 on admission. The patient had alcoholic liver cirrhosis and diabetes mellitus. He was diagnosed with hepatocellular carcinoma (HCC) at age 70 years and underwent transcatheter arterial embolization and radiofrequency ablation. At age 71 years, HCC recurred, and the patient underwent hepatic resection. Contrast-enhanced computed tomography (CT), echocardiography, and MRI showed a tumor measuring 5 cm in size located in the right ventricle. In addition, the tumor was enhanced heterogeneously on CT. On MRI, the tumor showed low intensity in the T1-weighted image and slightly high intensity in the T2-weighted image (Figure A). The tumor appeared the same as the myocardium on gadolinium-enhanced MRI and showed no enhancement in the late phase. Positron emission tomography CT showed abnormal intake (standardized uptake value, 7.3) of 18-fluoro-2-deoxyglucose at the right ventricle (Figure B). There was no tumor in the right atrium or inferior vena cava. With these findings of image studies and the medical history, we diagnosed isolated metastasis of HCC in the right ventricle, but surgical resection was not performed because of the fear of high risk of death. His dyspnea developed gradually, and he died 9 months after diagnosis. Autopsy revealed that a soft tumor filled the right ventricle (Figure C). There was a tumor measuring 5 cm in the lateral segment of the liver and many small metastases in both lungs. Histologically, the hepatic and right ventricular tumors were moderately differentiated HCC that invaded the myocardium but not the right atrium or inferior vena cava. Previous studies showed that the majority of metastatic sites of HCC are the lungs (18%–55%), lymph nodes (26.7%–53%), bones (5.8%–38%), and adrenal glands (8.4%–15.4%). Cardiac metastasis of HCC is rare, with a rate of 1.2% in autopsy. Majority of cardiac metastases are direct and continuous extensions of intrahepatic HCC, and isolated cardiac metastases that are discontinuous with intrahepatic HCC are exceedingly rare. Kawakami et al reported 17 cases of isolated cardiac metastases that were located in the right ventricle, right atrium, and left ventricle in 10 (58.8%), 5 (29.4%),