Hepatic pseudolymphoma: imaging features on dynamic contrast-enhanced MRI and diffusion-weighted imaging

Area of Science:

• Radiology
• Medical Imaging
• Hepatology

Background:

• Hepatic pseudolymphoma is a rare benign liver lesion.
• Accurate diagnosis can be challenging, often requiring differentiation from malignant tumors.

Purpose of the Study:

• To characterize the magnetic resonance (MR) imaging findings of hepatic pseudolymphoma.
• To evaluate the utility of dynamic contrast-enhanced (DCE) MR imaging and diffusion-weighted imaging (DWI) in diagnosing hepatic pseudolymphoma.

Main Methods:

• Retrospective analysis of MR data from 14 patients with histopathologically proven hepatic pseudolymphoma.
• Inclusion of dynamic gadopentetate dimeglumine-enhanced MR imaging and DWI.
• Qualitative and quantitative assessment of lesion morphology, signal intensity, enhancement patterns, and apparent diffusion coefficient (ADC) values.

Main Results:

• Lesions were typically round, small (mean 1.3 cm), homogeneous, hypointense on T1WI, and hyperintense on T2WI.
• All lesions demonstrated hypervascularity on DCE MR imaging with varied enhancement patterns.
• Significantly lower signal intensity than portal vein on arterial phase (P < 0.001) and lower ADC values than spleen (P = 0.012) were observed.

Conclusions:

• Hepatic pseudolymphoma commonly presents as a small, homogeneous, hypervascular nodule.
• Lower apparent diffusion coefficient (ADC) values compared to the spleen are a characteristic finding.
• Combined DCE MR imaging and DWI provide valuable features for diagnosing hepatic pseudolymphoma.