Epithelioid Hemangioendothelioma of Liver Origin that was Difficult to Diagnose: A Case Report

Abstract

A 71-year-old female patient presented to us with the chief complaint of epigastric pain. Abdominal computed tomography (CT) and magnetic resonance imaging (MRI) revealed evidence of chronic cholecystitis due to biliary calculi and a 30-mm mass in the S5 region of the liver. As definitive diagnosis by imaging examinations alone was difficult, we performed laparoscopic cholecystectomy for both treatment of the cholecystitis and diagnosis of the liver mass. The S5 region of the liver was atrophied and appeared scar-like. A layer that could be exfoliated easily remained between the gallbladder and this region. Additionally, rapid intraoperative histopathological examination of the gallbladder revealed the diagnosis of chronic cholecystitis, with no evidence of malignancy. Thus, the lesion was diagnosed as an inflammatory pseudotumor and the patient was followed up. Repeat CT scans performed at 2 and 5 months postoperatively indicated no changes in the shape of the mass. At 6 months after the surgery, a percutaneous liver biopsy was performed. Immunohistochemistry showed positive staining for vimentin and factor VIII. Based on the findings, the patient was diagnosed as having epithelioid hemangioendothelioma (EHE) primarily arising from the liver. At 8 months postoperatively, a laparoscopic-assisted S5 subsegmentectomy was performed.

Primary liver EHE occurs at a frequency of less than 1 in 1 million people, and it is difficult to make a definitive diagnosis preoperatively based on the imaging and macroscopic findings alone. In this case too, the final diagnosis was made by histopathological examination.