Solitary fibrous tumor of the liver: A case report and review of the literature

Abstract

Background: Hepatic solitary fibrous tumor (SFT) is a rare neoplasm. Up to now, only 90 cases have been reported in the English language literature. This report describes a case of SFT of the liver misdiagnosed as hepatocellular carcinoma.

Case summary: A 42-year-old male had a two-year history of a gradually enlarging intrahepatic nodule. The preoperative imaging revealed a mass with a size of 2.7 cm × 2.3 cm located in the segment IV of the liver. The patient was subjected to the resection of the segment IV, such as the medial segment of the left lobe of the liver. The histological examination of the mass showed various spindled cells irregularly arranged in the stroma. The immunohistochemistry of this mass revealed a positive staining for CD34 and STAT6. The history of intracranial tumor and postoperative pathological results led to the diagnosis of SFT of the liver (SFTL) due to a metastasis from the brain.

Conclusion: SFTL is an uncommon mesenchymal neoplasm that can be easily overlooked or misdiagnosed. The best treatment choice is the complete surgical resection of the mass. A regular follow-up after the surgery should be performed due to the poor prognosis of metastatic or recurrent SFT.

Keywords: Case report; Liver; Mesenchymal neoplasm; Metastasis; Solitary fibrous tumor; Surgical treatment.

Figure 1

Contrast-enhanced liver magnetic resonance. A: T1-weighted image showing a slight hypointense mass; B: Mass showing iso- to hyperintensity on T2-weighted image, and the size was 2.7 cm × 2.3 cm; C: Well enhanced mass in the arterial phase; D: lower intensity of the mass compared with the surrounding parenchyma during the portal venous phase; E: Diffusion-weighted imaging showing higher intensity of the mass compared to the normal liver tissue.

Figure 2

Images of the resected specimen. Gross specimen showing white-grayish cut surface with areas of necrosis and hemorrhage.

Figure 3

Postoperative pathology findings of solitary fibrous tumor. A: Proliferation of spindle cells randomly arranged in the abundant stromal collagen (hematoxylin and eosin staining, 200 × magnification); B: Immunohistochemical staining revealing the positive CD34 staining in the tumor cells (200 × magnification); C: Immunohistochemical staining showing a strong STAT6 expression in the nucleus (200 × magnification); D: Ki67 Labeling index of 10%-15% (200 × magnification).

Figure 4

Timeline of the patient’s medical history.