Liver Dysfunction Explains a Substantial Proportion of Circulating cfDNA Variability in HCC: An Exploratory Study

Introduction: Circulating cell-free DNA (cfDNA) has emerged as a promising minimally invasive biomarker in hepatocellular carcinoma (HCC), with potential applications in disease detection and prognostic stratification. This exploratory study aimed to evaluate the relationship between circulating cell-free DNA (cfDNA) concentration, liver dysfunction parameters, and hepatocellular carcinoma stage in an exploratory cohort: we sought to explore the extent to which cfDNA variability may be explained by the underlying liver disease environment and whether cfDNA concentration provides incremental information beyond routinely available markers of liver reserve for the discrimination between early- and late-stage hepatocellular carcinoma. Methods: Sixty-four newly diagnosed HCC patients were included. Clinical, laboratory, and staging data were collected. cfDNA was isolated from plasma, confirmed by on-chip electrophoresis, and quantified by fluorimetry. Logistic regression and ROC curve analyses were performed to assess the ability of several biomarker panels to discriminate early-stage HCC (BCLC 0-A) from intermediate/advanced-stage disease (BCLC B-D). Bootstrap resampling (2000 iterations) evaluated model robustness and coefficient stability. Additional linear regression analyses explored associations between cfDNA concentration and liver dysfunction parameters. Results: Linear regression demonstrated that liver dysfunction parameters explained approximately 53% of cfDNA variability, while HCC stage contributed minimally after adjustment. Models incorporating albumin, bilirubin, and platelet count as individual parameters demonstrated the best discriminatory performance after adjustment for liver disease etiology, achieving AUROCs up to 0.857. The only incremental value that cfDNA concentration added to the panel was an increase to its specificity (from 79.4% to 94.1%), while reducing sensitivity by 13.4%. Bilirubin and platelet count remained the most stable predictors after bootstrap, whereas cfDNA concentration was unstable. Limitations: The study was limited by its small sample size, cross-sectional design, and lack of longitudinal outcome assessment. External validation in larger prospective cohorts is necessary. Conclusion: A substantial proportion of cfDNA concentration variability (approximately 53%) was explained by routinely available liver dysfunction parameters, whereas HCC stage had minimal contribution. These findings suggest that circulating cfDNA concentration in patients with HCC may be influenced to a greater extent by the underlying cirrhotic liver environment and hepatocyte injury than by tumor burden alone. Integrated multimarker panels combining liver reserve parameters and liver disease etiology may be of interest for minimally invasive stratification of HCC. Although cfDNA concentration increased specificity for early- versus advanced-stage disease discrimination, its incremental value was low. Further validation in larger prospective cohorts is required.