微小血管侵襲陽性肝細胞癌患者に対する術後補助化学塞栓療法の選択的使用の可能性

Microvascular invasion (MVI) serves as a well-established prognostic factor for tumor recurrence and reduced survival following curative hepatectomy in hepatocellular carcinoma (HCC). This investigation aims to assess the therapeutic value of postoperative adjuvant transcatheter arterial chemoembolization (PA-TACE) in HCC patients with MVI and delineate the optimal patient subpopulations for this intervention.

This retrospective cohort study analyzed patients with MVI in HCC patients who received curative resection from September 2013 to June 2019. After balancing baseline differences between the PA-TACE group and the non-TACE control group using propensity score matching (PSM), the differences in recurrence-free survival (RFS) and overall survival (OS) between the two groups were compared. A multivariate Cox proportional hazards regression model was used to identify independent prognostic factors.

Among 440 evaluable patients, PA-TACE demonstrated statistically significant improvements in both RFS and OS compared to non-TACE management, with consistent results observed in both the entire and propensity score-matched cohorts. Multivariate analysis established PA-TACE as an independent protective predictor for both RFS and OS. Subgroup analyses revealed pronounced clinical benefits in patients exceeding Milan criteria and those presenting with high-risk features including serum AFP ≥400 ng/mL, tumor size ≥5 cm, Edmondson-Steiner grade III/IV differentiation, M2-type MVI, or major hepatectomy. Notably, no survival advantage was observed in patients within Milan criteria or BCLC-A/B stages.

PA-TACE provides substantial survival enhancement in HCC patients with MVI exceeding Milan criteria or with high-risk features, but offers limited benefit for Milan-eligible cases. Patient selection based on tumor biology is critical for optimizing adjuvant therapy.