Prognostic Impact of the Pathologic Response of Patients with Hepatocellular Carcinoma After Preoperative Treatments.

[BACKGROUND] Hepatocellular carcinoma (HCC) exhibits varying degrees of tumor regression after preoperative treatments. However, the relationship between a tumor residual and its impact on recurrence-free survival (RFS) remains poorly defined. This study aimed to assess the effect of pathologic response on RFS in HCC patients undergoing preoperative treatments.

[METHODS] Data from 400 patients with HCC who received preoperative treatments were retrospectively analyzed. The correlation between tumor residual and RFS was assessed using the "surv_cutpoint" function in R software and further validated through Cox proportional hazards regression models, with the objective of identifying a cutoff value that was significantly associated with RFS.

[RESULTS] The overall analysis showed that pathologic response significantly influenced postoperative recurrence when tumor residual of 15% or less was detected. Multivariate regression analysis found that the independent risk factors for RFS were pathologic satellite nodules (hazard ratio [HR], 1.56; 95% confidence interval [CI] 1.05-2.25; P = 0.047), microvascular invasion (HR, 1.72; 95% CI 1.16-2.55; P = 0007), and advanced tumor stage (HR, 1.60; 95% CI 1.05-2.44; P = 0.031). In contrast, an independent protective factor affecting RFS was found to be residual of 15% or less (HR 0.41; 95% CI 0.26-0.63; P < 0.001). Subgroup analyses showed that RFS was significantly associated with a tumor residual cutoff value of 15% in Barcelona Clinic Liver Cancer (BCLC) stage A, 20% in stage BCLC stage B, and 26% in stage BCLC stage C.

[CONCLUSIONS] This study demonstrated that achieving tumor residual of 15% or less after liver resection significantly reduces postoperative recurrence rates for HCC patients treated with preoperative therapies. The effect of tumor regression on RFS varied according to tumor stages.