The aMAP Score Effectively Stratifies Hepatocellular Carcinoma Risk in the Steatotic Liver Disease Population

Steatotic liver disease (SLD) is an increasingly important cause of hepatocellular carcinoma (HCC), yet validated risk stratification tools remain limited. We aim to evaluate the aMAP score, initially developed for HCC risk prediction mainly in viral hepatitis across international cohorts, in the SLD population.

156 406 SLD participants were included from the UK Biobank (UKB) and 3166 SLD patients with virally suppressed chronic hepatitis B from a Chinese cohort. The predictive and stratification performance of the aMAP score was assessed and compared with the PAGE-B, mPAGE-B, CAMD and MASLD-HCC scores. A refined stratification of the aMAP-defined high-risk population identified a subgroup exceeding the recommended surveillance threshold.

Median follow-up was 13.64 years in UKB and 9.97 years in the Chinese cohort, with 287 and 58 patients developing HCC, respectively. The aMAP score showed favourable discrimination (C-indices: 0.80 [95% CI, 0.78-0.83] in UKB; 0.79 [95% CI, 0.73-0.85] in the Chinese cohort). The 15-year cumulative HCC incidence by aMAP in UKB was 0.06% (95% CI, 0.04%-0.08%), 0.26% (95% CI, 0.21%-0.31%) and 1.43% (95% CI, 1.14%-1.72%) for low-, intermediate- and high-risk groups (high vs. low risk, sHR: 28.51; 95% CI, 19.58-41.52; Gray's test p < 0.001). Consistent results were found across etiological subgroups and in the other cohort (Gray's test p < 0.001). The refined cutoff (aMAP > 64) identified a very-high-risk subgroup in UKB with 15-year cumulative incidences of 3.08% (training; 95% CI, 1.29%-4.87%) and 5.35% (validation; 95% CI, 3.04%-7.67%).

The aMAP score is an effective tool for HCC risk stratification among SLD patients. The refined aMAP threshold accurately identifies very-high-risk patients qualifying for guideline-recommended surveillance.