Liver: tissue handling and evaluation.

Liver diseases remain among the most important causes of morbidity and mortality worldwide. Although the diagnostic tools (e.g., blood studies, imaging, genetic and molecular tests) available to clinicians have greatly expanded in number and increased in sensitivity, the examination of liver tissue by a pathologist skilled and experienced in hepatopathology remains vitally important in the evaluation and care of the patient with liver abnormalities. In some disorders, such as autoimmune hepatitis, liver biopsy is considered mandatory. The indications for performing liver biopsies have changed over the years (e.g., large duct obstruction was a common diagnostic problem 50 years ago and is only uncommonly so currently). Liver samples come to the pathologist as aspiration biopsies for cytologic examination, tissue biopsies (fine needle, core, transjugular, and wedge), resections, and explants. Each demands slightly different approaches for optimal handling and evaluation.