Ten years of Italian mini-invasiveness: the I Go MILS registry as a tool of dissemination, characterization and networking

Purposes of this study are to evaluate the main changes that have occurred in the Italian MILS activity in the last decade in terms of indications, approaches and outcomes as reported in the national registry and to provide specific details on the main areas of development of MILS. Data from patients undergoing minimally invasive liver resections at centers included in the I Go MILS Registry from its start-up (November 2014) to March 2023 were analyzed for the purposes of this study. The registry is intention-to-treat and prospective. Global recruitment trends stratified by indication to surgery and type of approach were analysed. 7413 MILS procedures were performed across all centers (median number of procedures per center: 63). Years (2020-2023) displayed a significantly higher proportion of treated patients diagnosed with hepatocellular carcinoma (HCC) (38.2% vs. 28.9% and 33.9%, p < 0.001) and cholangiocarcinoma (6.7% vs. 6.5% and 4.2%, p < 0.001) compared to the preceding triennial periods. Additionally, technical complexity demonstrated an increased prominence in Years (2019-2023) with a significantly higher percentage of grade III cases compared to the earlier periods (39.3% vs. 21.7% and 25.6%, p < 0.001). Annual case trends focusing on laparoscopic and robotic techniques demonstrated a steadily increase in the use of these techniques for complex case mix of indications. Overall, attitude and attention to MILS approach has evolved, so that currently indications to hepatic mini-invasiveness have expanded and surgical technique has been refined: Areas mainly involved in increasing growth trends are hepatocellular carcinoma, possible applications of MILS in transplant setting, intrahepatic cholangiocarcinoma and robotic approach.