Blood Tests and Liver-Stiffness Scans Could Spare Some Fatty-Liver Biopsies

Blood tests and liver-stiffness scans can identify advanced scarring and cirrhosis in metabolic fatty-liver disease accurately enough to reduce some reliance on biopsy, according to a large prospective international evaluation published in The Lancet on October 29. The same evidence also shows a harder limit: most non-invasive tools still cannot reliably diagnose active steatohepatitis, the inflammatory form targeted by new treatments.

One study, several levels of liver disease

Metabolic dysfunction-associated steatotic liver disease, or MASLD, is linked to metabolic risk factors such as obesity and type 2 diabetes. Fat can accumulate in the liver without obvious symptoms. Some patients then develop metabolic dysfunction-associated steatohepatitis, or MASH, in which inflammation and cell injury can drive fibrosis, cirrhosis and liver cancer.

A biopsy can reveal inflammation and the stage of scarring, but it requires a needle, samples only a small portion of the liver and is impractical for screening the large population at risk. The LITMUS study therefore tested whether blood markers and measures of liver stiffness could answer the most important diagnostic questions without removing tissue.

The main prospective, multicentre study included more than 1,500 patients and compared candidate tests with biopsies interpreted by expert pathologists. A companion imaging analysis evaluated magnetic resonance elastography, FibroScan-based measurements and serum markers in 357 participants who had both central biopsy reading and usable imaging data within six months.

Key Fact: The non-invasive tests were much better at finding advanced fibrosis and cirrhosis than at identifying active MASH, so “replacing biopsy” depends on the exact clinical question.

Which tests performed best?

For advanced scarring and cirrhosis, a SOMAScan protein panel, magnetic resonance elastography and FibroScan-based tools such as Agile 3+ produced the strongest results. The ELF and ADAPT blood tests also exceeded predefined performance thresholds for cirrhosis.

The researchers found a potentially useful low-cost first step as well. Gamma-glutamyl transferase, or gamma-GT, a routine blood measurement, outperformed the widely used FIB-4 score in this cohort. They propose that gamma-GT could flag people who need a second-stage ELF test or FibroScan, while expensive magnetic-resonance techniques remain concentrated in specialist care.

This is a triage pathway, not one universal replacement test. A cheap first-line marker can be valuable even if it is not definitive, provided that its thresholds safely direct higher-risk patients toward more accurate follow-up.

The inflammation problem remains

Diagnosing “at-risk MASH” proved more difficult. Of the tools assessed, only the SOMAScan panel met the predefined accuracy threshold for that target in the main study. The earlier imaging analysis similarly found that no imaging, serum or composite marker was sufficiently accurate to replace histology for diagnosing MASH across the cohort.

That distinction matters because recently approved treatments and late-stage clinical trials often target patients with active steatohepatitis and particular fibrosis stages. Regulators may still require biopsy confirmation when eligibility depends on proving both inflammation and scarring.

Why prospective validation matters

Many liver-test studies are retrospective, use selected populations or evaluate one product in isolation. LITMUS compared a broad set of routine and advanced tests prospectively across multiple countries and centres, using central pathology review as the reference.

The design makes the performance estimates more relevant to actual diagnostic pathways, but it does not automatically establish the best thresholds for every clinic. Disease prevalence, obesity, diabetes, scanner settings and referral patterns can change how many positive and negative results are correct.

What changes next?

The practical next step is to test staged pathways: an inexpensive blood marker first, a more specific blood or FibroScan assessment second, then specialist imaging or biopsy when results remain uncertain or treatment eligibility demands it.

The real measure of success will not be whether one test wins a ranking. It will be whether a validated sequence finds dangerous scarring earlier, reduces unnecessary biopsies and still avoids falsely reassuring patients whose disease needs specialist care.