Identification of candidates with hepatocellular carcinoma to receive TACE combined with MWA by assessing tumor burden and radiologic features.

Background: There is still no noninvasive, automated, and accurate model for guiding physicians in the decision-making of transarterial chemoembolization combined with microwave ablation (TACE-MWA) in intermediate-stage hepatocellular carcinoma (HCC).

Objectives: To develop a prognostic score based on the tumor burden and radiomic features for the prediction of the long-term survival of patients with intermediate-stage HCC after TACE-MWA.

Methods: From June 2008 to October 2022, a total of 2189 consecutive patients from seven tertiary-care hospitals with intermediate-stage HCC who received initial TACE combined with MWA were enrolled. Among them, 2189 were divided into training cohort (N = 1753), and internal test cohort (N = 436) in a single center, and 316 patients were assigned to external test cohort in another 6 centers. A prognostic scoring system was constructed using tumor burden and radiologic features (TBR) and compared with conventional predicting systems.

Results: In training cohort, multivariate Cox regression analysis suggested that tumor burden (hazard ratio (HR), 0.693; 95% confidence interval (CI): 0.505, 0.814; 1 point per 1.0 increase, p = 0.024), radiologic features (HR, 0.349; 95% CI: 0.236, 0.517; p < 0.001), and alpha-fetoprotein (HR, 1.629; 95% CI: 1.280, 2.073; p < 0.001) were independent prognostic factors for OS. A prognostic model that comprises TBR was built, which showed significantly higher AUC values than other clinical stagings in all three cohorts. Moreover, the TBR score provided greater net benefit across the range of reasonable threshold probabilities than other models. Based on cutoff values of 32 and 74 centiles of the TBR score, the cohort was divided into low-, middle-, and high-risk strata, which provide consistent performance in survival discrimination across different patient subgroups.

Conclusion: The TBR score serves as an efficient instrument for risk stratification, guiding the course of adjuvant targeted and immunotherapies for HCC patients undergoing TACE-MWA combined treatment.

Design: A retrospective, multi-institutional study.