Revisiting the role of postoperative adjuvant transarterial chemoembolization in hepatocellular carcinoma: a propensity score matching analysis.

Background: The optimal adjuvant therapy after liver resection in patients with hepatocellular carcinoma (HCC) is controversial. This study aimed to revisit the efficacy of postoperative adjuvant transarterial chemoembolization (PA-TACE) in HCC patients after curative-intent hepatectomy. Methods: A total of 387 patients were divided into PA-TACE group and no adjuvant treatment control group, and follow-up data were collected. The primary endpoints of recurrence-free survival (RFS) and overall survival (OS) were assessed before and after propensity score matching (PSM) analysis. Survival data were computed by means of the Kaplan-Meier method. Multivariable Cox proportional hazards model was used to determine the independent risk factors for patients' outcomes. Results: The RFS rates were higher in patients treated with PA-TACE compared to those in the control group, with borderline statistical significance [P=0.050; hazard ratio (HR) =0.75, 95% confidence interval (CI): 0.56-1.0]. Patients in the PA-TACE group had significantly higher OS rates than those in the control group (P=0.04, HR =0.70, 95% CI: 0.50-0.99). After PSM, the impact of PA-TACE on RFS and OS remained significant (HR =0.70, P=0.04 for RFS; HR =0.65, P=0.04 for OS). On multivariate Cox regression analyses in the entire cohort, age >65 years, γ-glutamyl transferase (GGT) >40 U/L, microvascular invasion (MVI)-positive, and no PA-TACE were identified as independent predictors for HCC recurrence. In further subgroup analysis, PA-TACE significantly improved RFS and OS of HCC patients in MVI-positive group (HR =0.31, P<0.001 for RFS; HR =0.47, P=0.002 for OS). The benefit of PA-TACE on RFS and OS remained significant in MVI-positive group after PSM (HR =0.32, P<0.001 for RFS; HR =0.38, P=0.003 for OS). Furthermore, patients who received PA-TACE developed recurrent HCC with less aggressive tumor characteristics. Conclusions: PA-TACE improves RFS and OS of HCC patients after liver resection, especially in MVI-positive patients. Furthermore, PA-TACE reduces the malignancy of recurrent tumors.