Primary hepatic lymphoma: report of two cases diagnosed by fine-needle aspiration

Primary hepatic lymphoma (PHL) is a rare disease which tends to progress slowly in the absence of other disorders and remains confined to the liver until late in its course. We report two patients with PHL diagnosed by fine-needle aspiration (FNA). Histopathologically, PHL can be misdiagnosed as poorly differentiated carcinoma or hepatocellular carcinoma. On FNA, cellular smears with artifactual grouping of malignant cells may result in similar errors. Since PHL has an excellent prognosis and is not usually the working diagnosis in patients who present with a solitary liver mass, a high index of suspicion is necessary to make the diagnosis. We report two cases of PHL in which the diagnosis of lymphoma was rendered on FNA. In one patient, who carried a clinical diagnosis of cavernous hemangioma for 18 mo, FNA showed large-cell lymphoma, B-cell type. Subsequent extensive workup did not reveal extrahepatic disease. The other patient, followed for sclerosing cholangitis, was clinically thought to have developed cholangiocarcinoma. FNA revealed high grade lymphoma, B-cell type. We present the clinical, radiologic, and pathologic findings and differential diagnoses of PHL as well as the various clinical settings in which PHL has been described.