Please explain how liver tissue is rated or graded after a biopsy. Is there a numerical scale to measure cirrhosis? I'm going to have a liver biopsy because of hemochromatosis, and would like to know what measurement or standards the pathologists use.

Pete

In a liver biopsy, doctors surgically remove a piece of liver tissue to examine more closely under a microscope. Usually, patients are referred for biopsy because of abnormal results on blood tests of liver function. Imaging studies may not be helpful or may show signs of diffuse liver injury, such as an enlarged liver or cirrhosis.

The biopsy is graded by two scoring systems. Both the degree of scarring (known as the "stage" of liver disease) and the degree of inflammation (known as the "grade" of disease) are noted. There are four stages. Stage 1 refers to a minimal amount of scarring, limited to an area of the liver known as the portal triad (where the arteries, veins and bile ducts are found). Further progression of scarring outside of the portal triad and into surrounding liver cells is considered stages 2 and 3. When scarring results in long bridges of fibrous tissue that separate nodules of normal liver tissue, it is called stage 4, or cirrhosis.

Liver disease also is graded on a scale of 1-4. In grade 1, there is minimal infiltration of inflammatory cells into the portal triad. As these cells spill over into the liver tissue from the portal triad, it is considered grades 2-3. Finally, large amounts of inflammation that involves all the liver is known as grade 4.

Hemochromatosis is a common genetic disease in which the liver accumulates excessive amounts of iron, leading to scarring and cirrhosis if it is not treated. When a biopsy is done for a patient with hemochromatosis, in addition to grading and staging the liver disease, the lab technician calculates the amount of iron in the sample. First, the sample is stained with a dye that is specific for localizing iron. Then, the iron deposition is graded on a scale of 1-4. Although some degree of iron deposition is seen in normal liver (grade 1-2 staining), in hemochromatosis this is increased and the iron is seen in cells that line small sinusoids (veins) near liver cells and in bile duct cells (grade 3-4 staining). The amount of iron is also quantified in the biopsy sample, and this is extrapolated to estimate how much excess iron is present in the liver. This calculation is helpful in guiding therapy (controlled blood donation) so that the appropriate amount of iron is eventually lost.