Multimodal imaging findings of primary liver clear cell carcinoma: a case presentation

Abstract

Primary clear cell carcinoma of liver (PCCCL) is a special and relatively rare subtype of hepatocellular carcinoma (HCC), which is more common in people over 50 years of age, with a preference for men and a history of hepatitis B or C and/or cirrhosis. Herein, we present a case of a 60-year-old woman who came to our hospital for medical help with right upper abdominal pain. The imaging examination showed a low-density mass in the right lobe of his liver. In contrast enhanced computed tomography (CT) or T1-weighted imaging, significant enhancement can appear around the tumor during the arterial phase, and over time, the degree of enhancement of the tumor gradually decreases. The lession showed obviously increased fluorine-18 fluorodeoxyglucose (¹⁸F-FDG) uptake on positron emission tomography/CT. These imaging findings contribute to the diagnosis of PCCCL and differentiate it from other types of liver tumors.

Keywords: MRI; PET/CT; clear cell carcinoma; imaging findings; liver.

Figure 1

(A) Abdominal computed tomography (CT) scan showed a circular low-density shadow near the gallbladder fossa in the right lobe of the liver (arrow); moreover, the volume of the left lobe of the liver increases, the ratio of the left and right lobes is unbalanced, and the widening of the liver cleft can also be seen, suggesting cirrhosis; (B) In the arterial phase of contrast-enhanced CT scan, the lesion showed uneven enhancement, mainly with peripheral enhancement of the lesion (arrow); During the portal vein phase (C) and delayed phase (D), the degree of enhancement of the lesion gradually declines (arrows).

Figure 2

On magnetic resonance imaging (MRI), the lesion showed equal signal on both in-phase (A) and out-phase (B) of T1-weighted imaging (T1WI, arrows), and uneven slightly higher signal on T2WI ((C), arrow). On contrast-enhanced T1WI, the lesion showed mild to moderate enhancement in arterial phase ((D), arrow), portal phase ((E), arrow) and delayed phase ((F), arrow), mainly peripheral enhancement.

Figure 3

(A) The maximum intensity projection of the positron emission tomography (PET)/computed tomography (CT) showed a lesion in the liver region with increased uptake of fluorine-18 fluorodeoxyglucose (¹⁸F-FDG), with a maximum standardized uptake value (SUVmax) of 8.5. Axial CT (B) showed the lesion in the right lobe of the liver (arrow). Axial PET (C) and PET/CT fusion image (D) showed obviously increased ¹⁸F-FDG uptake of the mass (arrows).

Figure 4

(A) Hematoxylin–eosin staining showed diffuse distribution of clear cells with abundant cytoplasm, centrally located nuclei and deep staining. Immunohistochemistry showed positive expression of tumor cells CK (B), Hep par1 (C), and Glypican (GPC3, (D)), HSP70 (partially, (E)), and Ki67 (about 40%, (F)). All images are 200 × magnification.