Epstein-Barr virus negative primary hepatic leiomyoma: case report and literature review

Abstract

Primary hepatic leiomyoma is a neoplasm of mesenchymal origin and occurs only rarely. Secondary to benign smooth muscle proliferation, it is usually found in adult women and is associated with Epstein-Barr virus (EBV) infection. Here, we report the 29(th) case of primary hepatic leiomyoma with its unique features related to diagnosis, treatment and developmental biology. A 48-year-old man, with an immunocompromised status, complained of pain in the upper quadrant of the abdomen. Serological analysis indicated no presence of hepatitis virus, no human immunodeficiency virus, and no EBV infection. The levels of α-fetoprotein and carcinoembryonic antigen were normal. A mass was detected in segment III of the hepatic lobe by ultrasonography and an abdominal computed tomography scan. Endoscopy had negative findings. Exploratory laparotomy found no existing extrahepatic tumor and left lateral lobectomy was performed. Pathological examination showed the mass to be a typical leiomyoma. The cells were positive for α-smooth muscle actin and desmin, and negative for the makers of gastrointestinal stromal tumor (GIST), including CD117, CD34 and DOG1 (discovered on GIST1). In situ hybridization revealed negative status for EBV-encoded small RNA. After left lateral lobectomy, the patient was not given chemotherapy or radiotherapy. During a 2-year follow-up, no sign of local recurrence or distant metastasis was observed. In conclusion, we report a rare case of primary hepatic leiomyoma in a male patient without EBV infection. Hepatic resection was curative. This case presents data to expand our knowledge concerning the complex and heterogeneous nature of primary liver leiomyoma, indicating that EBV infection is important but neither necessary nor sufficient for the development of primary liver leiomyoma.

Keywords: Cancer diagnosis; Developmental biology; Epstein-Barr virus; Primary hepatic leiomyoma; Tumor resection.

Figure 1

Abdominal computed tomography scan shows a mass in segment III of the liver. A: Hepatic equilibrium phase; B: Portal venous phase; C: Hepatic arterial phase. The arrows indicate the tumor in the liver.

Figure 2

Pathological characteristics of the primary liver leiomyoma. A: Tumor (arrow) located in segment III of the liver; B: Tumor (arrow) and normal liver tissue, hematoxylin and eosin staining, × 200; C: α-smooth muscle actin staining (arrow) of tumor tissues, immunohistochemical staining, × 200; D: Desmin staining (arrow) of tumor tissues, immunohistochemical staining, × 200.

Figure 3

Tumor cells stained negative by in situ hybridization with Epstein-Barr virus-encoded small RNA. A: Positive control staining × 200, × 1000; B: Tumor cell staining × 200, × 1000. Arrows indicate positive staining of the nuclei.