Primary liver lymphoma in a patient with chronic hepatitis C.

Primary liver lymphoma is a very rare disease and is frequently overlooked as a possible diagnosis. We report the case of an asymptomatic middle-aged man with chronic hepatitis C who developed primary liver lymphoma (PLL). A large solitary tumor in the left lobe of the liver was incidentally detected on routine ultrasound examination. Imaging studies showed mixed iso- and hypoechogenicity with hypoechoic rim, hypodense in the pre-contrast phase and thick wall enhancement in the post-contrast phase on computed tomographic study, hypointensity on T1WI, and hyperintensity of the central portion and slightly higher intensity in the peripheral wall on T2WI. These pictures were different from focal nodular hyperplasia, hepatocellular carcinoma, cholangiocarcinoma or metastases. Atypical hepatectomy was performed and the pathology of the hepatic tumor revealed non-Hodgkin's lymphoma. Systemic staging revealed no evidence of nodal or bone marrow involvement, so PLL was diagnosed. There was no tumor recurrence more than 4 years after operation and chemotherapy. PLL should be included in the differential diagnosis of solitary hepatic tumor in patients who are hepatitis C virus-positive, and who have atypical imaging and no known malignancy or elevated tumor marker levels.