Role of Contrast-Enhanced Ultrasonography in Primary Hepatic Lymphoma

Objective. Ultrasonography is the first examination performed for screening of hepatocellular carcinoma (HCC); contrast-enhanced ultrasonography (CEUS) can help discriminate between HCC and other lesions. Primary hepatic lymphoma (PHL), even if rare, should be considered in the differential diagnosis of focal liver lesions (FLLs). Few data are available in the literature about the role of CEUS in the diagnosis of PHL; we tried to determine whether CEUS could have a role in this setting. Methods. we describe 2 cases of primary non-Hodgkin lymphoma of the liver associated with hepatitis B virus (HBV) infection. The first patient was a 62-year-old man who was an HBV-inactive carrier, and the second was a 58-year-old man with type 2 diabetes and chronic HBV hepatitis. Results. in both cases, ultrasonography showed a hypoechoic liver lesion (4 and 3 cm, respectively) with irregular margins in segment 4 of the liver. On CEUS, these lesions were inhomogeneously hyperenhanced in the arterial phase and hypoenhanced in the portal and late phases. Contrast-enhanced computed tomography (CT) in both patients showed slight hyperenhancement in the arterial phase and hypoenhancement in the remaining phases. Needle biopsy showed marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue type in both patients. Conclusions. Contrast-enhanced ultrasonography and CT did not help us differentiate PHL from HCC; in fact, in both cases we saw the characteristic findings of primary HCC. Primary hepatic lymphoma is a rare condition, but it should always be considered in the differential diagnosis of FLLs. We stress the important role of liver biopsy when imaging indicates HCC in patients without underlying cirrhosis.