Phase 3 validation of PAaM for hepatocellular carcinoma risk stratification in cirrhosis

Background and aims

Hepatocellular carcinoma (HCC) risk stratification is an urgent unmet need for cost-effective HCC screening and early detection in patients with cirrhosis to improve poor HCC prognosis.

Methods

Molecular (Prognostic Liver Secretome signature with alpha-fetoprotein) and clinical (aMAP score) variable-based scores were integrated to develop PAaM, which was subsequently validated in two phase 3 biomarker validation studies: the statewide Texas HCC Consortium (THCCC) and nationwide HCC Early Detection Strategy (HEDS) prospective cohorts, following the prospective specimen collection, retrospective blinded evaluation (PRoBE) design. The associations between baseline PAaM and incident HCC were assessed using Fine-Gray regression, with overall death and liver transplantation as competing events.

Results

Of 2,156 cirrhosis patients in THCCC, PAaM identified 404 (19%) high-risk, 903 (42%) intermediate-risk, and 849 (39%) low-risk patients with annual HCC incidence rates of 5.3%, 2.7%, and 0.6%, respectively. Compared to low-risk patients, high- and intermediate-risk groups had sub-distribution hazard ratios (sHRs) for incident HCC of 7.51 (95% confidence interval [CI], 4.42-12.8) and 4.20 (95%CI, 2.52-7.01), respectively. Of 1,328 cirrhosis patients in HEDS, PAaM identified 201 (15%) high-risk, 540 (41%) intermediate-risk, and 587 (44%) low-risk patients, with annual HCC incidence rates of 6.2%, 1.8%, and 0.8%, respectively. High- and intermediate risk groups were associated with sHRs for incident HCC of 6.54 (95%CI, 3.85-11.1) and 1.77 (95%CI, 1.02-3.08), respectively. Subgroup analysis showed robust risk stratification across HCC etiologies, including metabolic dysfunction-associated steatotic liver disease (MASLD) and cured hepatitis C infection.

Conclusion

PAaM enables accurate HCC risk stratification in patients with cirrhosis from contemporary etiologies.