Defining the role of minimally invasive surgical thermal ablation in liver malignancies: A systematic review and meta-analysis of outcomes and reporting standards

Malignant liver tumors are increasingly treated with thermal ablation. Minimally invasive surgical thermal ablation (MITA) may offer advantages over the percutaneous approach for lesions near critical structures. This systematic review and meta-analysis evaluated the safety, technical success, and long-term oncological outcomes of laparoscopic and robotic MITA, synthesizing data from 28 studies encompassing 3983 patients and 7033 treated lesions. Overall, 3959 procedures were carried out laparoscopically, while 24 were performed with a robotic approach. The primary analysis demonstrated a pooled technical failure rate of 2% (95% CI 1-4%), with a significant improvement to 1% in studies published after 2017, reflecting progressive technical refinement. Major complications (Clavien-Dindo ≥ 3a) occurred in 2.2% of cases (95% CI 1.4-3.5%), with a 30-day mortality of 0.25% (95% CI 0.08-0.75%). The aggregated incidence rate of local tumor progression was 6.13 events per 100 person-years, highlighting a discrepancy between immediate technical success and durable local control. For hepatocellular carcinoma, 1-, 3-, and 5-year OS were 90%, 69%, and 45%, with DFS of 74%, 48%, and 29%. For colorectal liver metastases, 1-, 3-, and 5-year OS were 90%, 60%, and 43%, and DFS were 66%, 60%, and 43%. MITA is a safe option for tumors unsuitable for percutaneous treatment, with very low procedure-related morbidity and mortality. However, high technical success does not always translate into durable local control, and current evidence is limited by heterogeneous reporting standards. Multicenter RCTs and standardized outcome definitions are needed to strengthen the evidence base and refine clinical guidelines.