[NATAP] Liver Biopsy vs BioMarkers in HCV

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NATAP - http://www.natap.org

Staging Liver Fibrosis: Time to Abandon Liver Biopsy?

August 07, 2005

Nezam H. Afdhal, MD

Chief of Hepatology

Beth Israel Deaconess Medical Center

Associate Professor of Medicine

Harvard Medical School

http://clinicaloptions.com/hep/ev/2005-6.asp

Additional reading referred to in article by Afdahl:

Noninvasive markers of hepatic fibrosis: Are they ready for prime time in the management of HIV/HCV co-infected patients? - (06/23/05)

http://www.natap.org/2005/HCV/062305_02.htm

Predicting cirrhosis in patients with hepatitis C based on standard laboratory tests: Results of the HALT-C cohort (08/05)

http://www.natap.org/2005/HCV/072105_09.htm

The established gold standard for the evaluation of liver disease has traditionally been a percutaneous liver biopsy. Liver biopsy is used predominantly for the diagnosis, prognosis, and staging of liver disease. Despite improvements in serologic diagnostic tests for liver disease, a biopsy is often still indicated to make the diagnosis of many forms of liver disease. Biopsy is also useful for determining prognosis, usually by confirming the presence or absence of cirrhosis. More recently, biopsy has been used for staging fibrosis in viral hepatitis and for decision analysis as to the need for treatment. Many treatment algorithms recommend treatment for patients with septal fibrosis or greater (≥ METAVIR stage 2). Improvement in either tolerability or efficacy of therapy could easily alter this current treatment paradigm, increasing physician and patient acceptability of therapy and reducing the need for liver biopsy.

Liver biopsy is rarely associated with severe complications in this era of ultrasound guidance or marking, and bleeding is rare (1:10,000 biopsies).[1] The major issues with biopsy are cost (approximately $2200) and patient acceptability and anxiety. In addition, recent studies have suggested that biopsy is only about 80% accurate in the staging of liver fibrosis and may even miss advanced fibrosis or cirrhosis in 30% of patients. The factors associated with the inaccuracy of biopsy include the heterogeneous nature of liver disease, the relatively small size of a biopsy compared to the size of the liver, and the experience of the pathologist. This has led to the concept that a liver biopsy should be at least 25 mm in length to reduce the sampling error.[2] Although this is a noble aim pathologically, it remains a clinical rarity, with only 20% of liver biopsies even approaching this length.

These limitations of biopsy have led clinical investigators to study alternative methods to stage liver disease. Noninvasive serum biomarkers are the most widely used alternative to liver biopsy and have recently been reviewed.[3] There are 2 major types of biomarker tests, those that use clinical variables to stage fibrosis and those that use extracellular matrix (ECM) markers.[4,5] There are advocates of specific tests, but overall the performance characteristics of all these tests are relatively similar