Non-invasive assessments for liver fibrosis: The crystal ball we long for

Non-invasive assessment of liver fibrosis has been one of the most rapidly advancing fields in hepatology in the last decade. Progressive liver fibrosis results in cirrhosis, hepatocellular carcinoma (HCC), and various liver-related complications in essentially all chronic liver diseases. Assessment of liver fibrosis allows clinicians to determine the prognosis, need of treatment, disease progression, and response to treatment in patients with chronic liver disease. Liver biopsy has been the gold standard in last few decades and most adopted diagnostic tool in clinical trials. Nonetheless, it is impractical to apply the test in a large number of patients or to do it serially. Hence, various non-invasive assessments have been developed and adopted in some international management guidelines. Liver stiffness measurement (LSM) with transient elastography is one of the most widely validated non-invasive assessments for liver fibrosis. It is an accurate and reproducible method to predict advanced fibrosis in chronic hepatitis B. Using transient elastography, it is possible to perform repeated liver fibrosis assessments on a large number of asymptomatic patients. The key challenge of his tool is the confounding effect of alanine aminotransferase (ALT) level, such that decrease in LSM may only reflect ALT normalization, hence not accurate enough to indicate regression of liver fibrosis. This may be partially handled by combining LSM with a serum-based formula, which is independent of ALT such as the Forns index and enhanced liver fibrosis test. An LSM-based HCC risk score is useful to prioritize patients for HCC surveillance.