Main outcomes and measures: Separate ML models estimating 3-year overall survival (OS) were developed for LT and SR. Patients were stratified into high- and low-risk groups for each treatment, identifying LT-favorable and LT-nonfavorable groups. Counterfactual analysis evaluated OS differences between ML-guided and clinical practice treatments.
Results: A total of 3915 patients (3137 [80.1%] male), 296 in the LT group (median [IQR] age, 54.0 [49.0-60.0] years) and 3619 in the SR group (median [IQR] age, 58.0 [51.0-66.0] years), were included in the derivation cohort, and 614 patients (497 [80.9%] male)-314 in the LT group (median [IQR] age, 55.0 [51.0-60.0] years) and 300 in the SR group (median [IQR] age, 59.0 [52.0-66.0] years)-were included in the external validation cohort. Across both cohorts, LT recipients were generally younger and had more advanced liver disease, with higher rates of cirrhosis (78 [26.4%] vs 699 [19.3%]; P = .005), hepatic encephalopathy (20 [6.8%] vs 10 [0.3%]; P < .001), and ascites (50 [19.9%] vs 153 [4.2%]; P < .001). LT recipients also exhibited poorer liver function, with lower albumin levels (median [IQR], 3.4 [2.8-4.0] vs 4.2 [3.9-4.5] g/dL), higher bilirubin levels (median [IQR], 1.4 [0.9-2.5] vs 0.7 [0.5-1.0] mg/dL), and prolonged international normalized ratios (median [IQR], 1.2 [1.1-1.5] vs 1.1 [1.0-1.1]), and had smaller tumors (median [IQR], 2.3 [1.5-3.6] vs 3.2 [2.2-5.0] cm; P < .001) but more tumors (mean [SD], 1.6 [1.0] vs 1.2 [0.7]; P < .001). The support vector machine model achieved the highest area under the receiver operating characteristic curve (AUROC) of 0.82 (95% CI, 0.78-0.86) in the LT cohort, whereas CatBoost performed best in the SR cohort (AUROC, 0.79 [95% CI, 0.78-0.80]). Counterfactual analysis estimated that ML-guided treatment decisions could improve survival compared with observed clinical practice decisions (HR, 0.46 [95% CI, 0.42-0.50]; P < .001). These findings were consistent in the independent cohort.
Conclusions and relevance: Findings from this cohort study of patients with HCC indicated that an ML-based decision-support model estimated accurate risk stratification and identified the potential for improved survival through individualized, model-guided treatment selection. These findings suggest clinical utility in supplementing existing guidelines.