Circulating cell-free DNA methylation signatures in metabolic dysfunction-associated steatotic liver disease: Emerging biomarkers for disease diagnosis, progression, and non-invasive monitoring

Metabolic dysfunction-associated steatotic liver disease (MASLD) is an umbrella term for a chronic liver condition characterized by hepatic fat accumulation with at least one cardiometabolic risk factor and no other known predominant cause of hepatic steatosis. Driven by the steadily increasing prevalence of obesity and insulin resistance, the global burden of MASLD continues to rise. Often undiagnosed and therefore left untreated, this condition can progress to metabolic dysfunction–associated steatohepatitis (MASH), cirrhosis, and ultimately to liver failure, decompensated cirrhosis, or hepatocellular carcinoma. For this reason, early diagnosis of active disease is essential for timely therapeutic intervention. Despite several shortcomings, liver biopsy remains the reference method for the histological assessment of steatohepatitis and fibrosis, and for monitoring therapeutic response. This review discusses the rationale for non-invasive diagnostic approaches for detecting and monitoring early-stage MASLD. Circulating cell-free DNA (cfDNA) methylation profiling is emerging as a near-real-time analytical method that reveals dynamic tissue-specific epigenetic alterations during MASLD progression. Considering the complexity of MASLD pathogenesis, this review also proposes integrating multi-omics modalities with cfDNA methylation to improve diagnostic accuracy.