Diagnostic value of albumin gene expression in liver tumors: case report and review of the literature.

Management of a solitary liver mass necessitates reliable distinction between primary hepatocellular carcinoma and metastatic lesions. The histologic differentiation can be difficult even with special stains such as alpha-fetoprotein, cytokeratin, and carcinoembryonic antigen. Albumin is a specific product of hepatocytes, and in situ hybridization to reveal albumin messenger RNA (mRNA) is highly specific and sensitive for the diagnosis of primary hepatocellular carcinoma. This technique can be used on histopathologic specimens and in cytologic diagnosis. Herein we describe a patient with synchronous renal and hepatic masses, in whom the distinction had to be made between metastatic renal cell carcinoma and two separate primary tumors--one in the liver and one in the kidney. In situ hybridization for albumin mRNA proved helpful in making this distinction. In addition, we review the literature on the diagnostic use of albumin gene expression in liver tumors.