Microwave ablation vs. surgical resection for treatment naïve hepatocellular carcinoma within the Milan criteria: a follow-up of at least 5 years

Objective: Thermal ablation poses challenges in the surgical resection (SR) of small hepatocellular carcinoma (HCC), and its therapeutic outcomes for larger lesions remain debated. Methods: This retrospective study evaluated 729 patients with HCC meeting the Milan criteria, who were treated with curative SR or microwave ablation (MWA) between 2008 and 2014. Overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS), and local tumor progression (LTP) were compared after propensity score matching (PSM). Co-variates associated with OS, CSS, LTP, and DFS were identified. The risk of death and tumor progression were compared. Results: During the median follow-up of 78.6 months, 253 patients were included in each group after PSM. For tumors ≤ 3.0 cm and 3.1–4.0 cm, MWA achieved comparable results in terms of OS, CSS, DFS, and LTP. For tumors 4.1–5.0 cm, MWA had lower OS, CSS, and DFS rates (all P < 0.05) than SR. Higher LTP rates were observed in the MWA group for tumors 4.1–5.0 cm, although the difference was not significant (P = 0.18). Complication rates (P = 0.41) were similar, but MWA led to less estimated blood loss (P < 0.01) and shorter postoperative hospitalization times (P < 0.01). Conclusions: MWA achieved comparable long-term oncologic outcomes with SR for ≤ 4 cm HCC, with lower complication rates and faster recovery.