APASL 2020 | Prof.Castera: The advantages of noninvasive assessment of liver fibrosis are more and more obvious

Editor: Jiamo Ren Date:2020/07/24

Noninvasive assessment and diagnosis of liver fibrosis have been developed rapidly in recent years. Compared with liver biopsy, they are safer, more convenient and can be repeated many times. They have been widely used in clinical practice.

At the 29th Annual meeting of the Asian-Pacific Association for the Study of the Liver (APASL2020), the journalist in front of Hepatology Digest had the honor to invite Professor Laurent Castera, former Secretary General of The European Association for the Study of the Liver (EASL) and Professor of The Seventh University of Paris to give an interview and ask him to share non-invasive testing technology and cutting-edge views.

The details are as follows.

<Hepatology Digest> : What are the main advances in non-invasive assessment of hepatic fibrosis in the last decade?

Dr. Castera : Non-invasive assessment of liver fibrosis has been one of the major advances in hepatology that really revolutionized the management of patients with liver disease worldwide. Actually, it all started in France about 15 years ago with two different approaches but complementary. The first approach was based on the dosage of serum biomarker; and the second approach was based on the measurement of liver stiffness using elastography technique for which FibroScan has been the pioneer. So, one of the major advantages of transient elastography is that it is a point of care technique that can be performed in the outpatient clinic or at bedside with immediate results. This is the most validated technique worldwide and now it is used in every liver clinic over the world including in the US, where it has been approved by the FDA in 2013, of I recall well. To stratify patients, when you see patients with liver disease, this is what you are using, transient elastography. If you are above 10 kPa on a scale that goes from 2 to 75, you are likely to have compensated chronic advanced liver disease, pre-cirrhotic. And if you are above 15, your likelihood is even higher. So, above 15 the probability of having what was called cirrhosis, compensated cirrhosis, is close to 90%. However, you need to be aware that the risk of false positive is higher than the risk of false negative. In other words, these techniques are better at ruling out than ruling in cirrhosis. Why? Because inflammation for instance with diabetes b may be associated with false positive cases, also the patients should be fasting otherwise there is risk of false positive, and if you have acute inflammation or acute hepatitis, or like we see in hepatitis B when there’s 20 minutes flare above 10 times the upper limit of normal there is a risk of false positive. Last but not least, operatory experience is also important, and has to be taken into account.  

<Hepatology Digest>:What are the factors associated with the accuracy of non-invasive assessment of hepatic fibrosis?

Dr. Castera :The major limitation of transient elastography, as I mentioned before, apart from the other factors, is obesity. And as you know, now, worldwide the leading cause of liver disease is becoming NAFLD, non-alcoholic fatty liver disease, it is more predominant in Western countries than in Eastern countries and in Asia, but still the prevalence is increasing fast. When transient elastography started with a regular probe this was an issue for applicability, and applicability was around 80%, now, this has been solved with a new XL probe the applicability is very high, is around 97%. So, 3% of failure rate in other words, and again this is a very interesting tool to stratify your patients in the clinic. Also, what it is important in patients with cirrhosis, compensated cirrhosis, you might be able to predict decompensation according to the value of liver stiffness and for instance I mentioned the value ran from to 2 to 75 kPa, if you are below 20 kPa most patients will be compensated, and let say you are above 50 kPa, so from 50 – 75 kPa most patients will have already experienced complications. In between 20 – 50, this is a gray zone, it is a very useful tool in your clinical practice to stratify the risk of your patients in terms of complications, occurrence of complications liver related, but also mortality. 

<Hepatology Digest>: Is there still a role of liver biopsy for the assessment of liver fibrosis? When should liver biopsy be considered for patients with liver disease?

Dr. Castera : Of course, the number of liver biopsy has been really reduced since the introduction of this non-invasive method, but there is still, I think, a place for liver biopsy. So, for instance, if you are using several non-invasive tests, let’s say serum marker and transient elastography, when there is discordance you might use liver biopsy to resolve the discordance issue. Also, in NAFLD if you need to make a diagnosis of NASH so the active component of the disease non-alcoholic steatohepatitis with inflammation, this cannot be done with this method, and then you might need a liver biopsy. For instance, currently with all the ongoing therapeutically trials in NAFLD, liver biopsy is still mandatory, first to know whether there is NASH or not, and second to assess the disease severity in terms of fibrosis stage. So, there is still a place for liver biopsy in these patients.