Laparoscopic vs Open Surgery for Colorectal Liver Metastases

IMPORTANCE Surgery represents the mainstay treatment of colorectal liver metastases. Indications for the laparoscopic approach in this setting have been widened and there is a need to confirm the benefits of minimally invasive liver surgery (MILS) in patients with complex disease states. OBJECTIVE To compare outcomes of laparoscopic surgery with those of open surgery for liver metastases from colorectal cancer, focusing on the characteristics of modern MILS and therefore overcoming possible selection bias related to different policies for patients' eligibility for MILS over time. DESIGN, SETTING, AND PARTICIPANTS A cohort study of 885 resections performed for liver metastases from colorectal cancer between January 1, 2004, and June 30, 2017, at the Hepatobiliary Surgery Unit of San Raffaele Hospital, Milano, Italy, comprising 187 laparoscopic and 698 open resections. Procedures performed using the MILS approach with a ratio of MILS to total resections per year of more than 30% were considered and were matched by propensity scores (ratio of 1:4) to procedures performed using the open approach with a ratio of MILS to total resections per year of less than 30%. MAIN OUTCOMES AND MEASURES The primary end point was short-term outcomes, including morbidity, mortality, functional recovery, and interval between surgery and adjuvant treatments; the secondary end point was long-term outcomes. RESULTS Among this cohort (104 patients in the MILS group; 46 women and 58 men; median age, 62 years [range, 35-81 years]; and 412 patients in the open group; 181 women and 231 men; median age, 60 years [range, 37-80 years]), primary end-point data showed a significantly higher incidence of postoperative morbidity in patients who underwent open resections compared with those who underwent MILS (94 [22.8%] vs 21 [20.2%]; P = .04). Patients in the MILS group had fewer major complications (Dindo-Clavien grades III-V) compared with patients in the open group (Dindo-Clavien grades III-V; 7 [6.7%] vs 35 [8.5%]; P = .03) as well as shorter lengths of stay (median [range] duration, 3 [2-35] vs 5 [4-37] days; P = .02). Oncologic results were not compromised by the laparoscopic approach. CONCLUSIONS AND RELEVANCE In this study, the results of the propensity score matching analysis between modern laparoscopic surgery and previous open surgery appear to confer more comparable cohorts for complexity, further supporting the advantages of laparoscopy in the surgical treatment of liver metastases from colorectal cancer. The increase in use that laparoscopy has experienced appears to be based on increased feasibility, widening of eligibility criteria for patients, enhanced clinical effectiveness, and oncologic outcomes. All these elements together suggest that up to 70% of patients appear to be candidates for this minimally invasive surgical approach in high-volume centers.