2340 Almost Fatal: An Unusual Case of Focal Nodular Hyperplasia in Cirrhotic Liver Mimicking Cholangiocarcinoma

Abstract

INTRODUCTION: Focal nodular hyperplasia is a benign tumor of the liver, second most common after hemangioma. Most commonly, it is incidentally found in reproductive-aged women. It accounts for 8% of all primary liver tumors. Radiologically these regenerative nodules closely mimic intrahepatic cholangiocarcinoma and may be misdiagnosed leading to fatal outcomes. In most cases, the histopathological examination of a biopsy specimen establishes a definitive diagnosis. It is a rare entity for FNH to present in cirrhotic liver and as multiple nodular lesions (>5 in number). CASE DESCRIPTION/METHODS: An obese 66-year-old woman with a past medical history of diabetes presented with recurrent episodes of hematemesis and melena. Physical examination revealed a soft abdomen with hepatomegaly. Laboratory examination revealed microcytic anemia with hemoglobin of 7.1 g/dL and MCV of 73 fL. Liver function tests were within normal limits. Esophagogastroduodenoscopy revealed bleeding medium sized gastric body ulcer which was clipped. Abdominal computed tomography (Fig. A) and Magnetic resonance imaging (Fig. B) revealed multiple ( >5) ill-defined slow enhancing liver lesions, the largest of which measured 5.7 × 7.8 × 7.4 cm mass. Hepatitis screen and tumor markers including CA 19-9, CEA, AFP were negative. Liver cirrhosis was thought to be secondary to nonalcoholic steatosis as her work up did not reveal any other cause. Magnetic resonance cholangiopancreatography (Fig. C) revealed cirrhotic liver and multifocal lesions including a 9 × 8.1 × 11.9 cm mass in the right lobe and additional multiple small lesions in the left lobe all showing a rim of enhancement in the arterial phase, centripetal enhancement in venous phase, delayed washout in late phase and with associated overlying capsular retraction. Biopsy of the liver lesions revealed focal nodular hyperplasia with underlying fibrosis (Fig. D, E). with no evidence of malignancy. Our case is a very rare mimic of multifocal cholangiocarcinoma due to similarities radiologically which without a biopsy could have led to a misdiagnosis and wrong management. DISCUSSION: FNH usually presents as a single lesion in a normal liver parenchymal tissue. When diagnosed and symptomatic, treatment modalities include surgical removal or in some cases, trans-arterial chemoembolization. Our patient is a very unique case of FNH presenting as multinodular lesions in a cirrhotic liver. Since she remains asymptomatic, she will be actively monitored with a regular ultrasound screening.