Downstaging therapy of intermediate-stage hepatocellular carcinoma: microwave ablation vs. surgical resection

Transarterial chemoembolization(TACE) is a potential downstaging therapeutic strategy for intermediate-stage hepatocellular carcinoma(HCC). However, therapeutic options following conversion therapy is still controversial.

This study aimed to compare the efficacy and safety of surgical resection(SR) and microwave ablation(MWA) following TACE based downstaging therapy for intermediate-stage HCC.

From January 2008 to December 2021, a total of 2,125 consecutive patients with intermediate-stage HCC underwent initial TACE at seven hospitals were identified. Among them, 554 eligible HCC patients occurred objective response(OR) to TACE, who meet the tumor burden equivalence of early-stage disease. The propensity score matching(PSM) was applied to reduce selection bias. The overall survival(OS) and recurrence-free survival (RFS) were compared using the Kaplan-Meier method with the log-rank test. Independent risk factors for survival outcomes were identified through multivariable Cox analyses using forward stepwise regression.

After PSM 1:1, 152 patients in MWA group were matched with those in SR group. SR demonstrated comparable long-term survival outcomes (5-years OS rate, 85.3% vs 82.5% and 5-years RFS rate, 77.2% vs 75.0%) than MWA. Multivariate analyses showed that the factors that significantly affected the OS were Body Mass Index (hazard ratio[HR]:0.61;95% confidence interval [CI]: 0.37-0.82). Multivariate analyses showed that the interval between local-region treatment and TACE (HR:0.41; 95% CI: 0.24-0.67), HBV (HR: 0.32; 95% CI: 0.15-0.69) and systemic treatment (HR:0.44; 95% CI: 0.25-0.76) significantly affected the RFS.

MWA might be acceptable as an alternative to SR in first-line TACE based downstaging therapeutic scheme for patients with intermediate-stage HCC.