Based on the results of a large retrospective study comparing laparoscopic liver surgery and robotic liver surgery, is it time for the next step in robotic liver resection?

We read with great interest the article by Sijberden et al., published in a recent issue of Annals of Surgery (1). The authors compared the perioperative outcomes of robotic liver surgery (RLS) and laparoscopic liver surgery (LLS) in an international retrospective cohort study.

Over the past two decades, minimally invasive liver surgery (MILS) has significantly grown in adoption, with the efficacy of LLS evaluated in both observational and randomized studies. The use of RLS is increasing owing to its visualization, surgical precision, greater institutional availability, and dexterity in MILS (2). However, evidence supporting its implementation remains relatively scarce, and the associated costs are generally higher than those of LLS (3). Therefore, large-scale studies are necessary to validate the benefits of RLS.

This study included 10,075 patients, with 1,507 undergoing RLS and 8,568 undergoing LLS. After propensity score matching, both the RLS and LLS groups included 1,505 patients. As the largest cohort study to date, it utilized prospectively maintained databases from 34 hepatobiliary referral centers across 15 countries. To evaluate the postoperative course after LLS or RLS, the authors defined a “textbook outcome in liver surgery” (TOLS) (4) as the absence of intraoperative incidents of grade 2 or higher, postoperative bile leak grade B or C, severe morbidity, readmission, and 90-day or in-hospital mortality, and the presence of an R0 resection margin in case of malignancy. The absence of a prolonged length of stay was added to define TOLS+, using previously reported cutoffs of >4 and >7 days for minor and major resections, respectively.

The study showed excellent outcomes for both LLS and RLS, with RLS achieving slightly higher TOLS rates than LLS. Analysis of intraoperative outcomes indicated that RLS was associated with reduced Pringle usage, shorter operative times and shorter Pringle duration, and less blood loss, transfusions, severe intraoperative incidents, and conversions. Postoperatively, RLS was linked with reduced rates of overall morbidity, lower R1 resections, and higher TOLS and TOLS+ achievement.

We believe certain aspects of this study warrant further discussion and analysis.

The study period spanned more than 10 years [2009–2021], and RLS may have been performed more frequently in recent years. Consequently, improvements in perioperative care and practice during this period may have influenced the observed outcomes. Although propensity score matching was employed, biases related to the study’s retrospective nature likely persist. To address this limitation, the authors performed a sensitivity analysis, comparing both approaches from January 2015 onwards, matching 1,394 patients who underwent RLS to 1,394 patients who underwent LLS. This analysis confirmed comparable benefits of RLS over LLS, with a higher TOLS rate observed with RLS. Additionally, the impact of the learning curve warrants consideration. Generally, surgeons performing RLS are experienced in LLS, potentially leading to bias since these surgeons may have greater expertise in MILS than those performing only LLS. This may explain the higher conversion rate in the LLS group, even among patients who underwent minor resections in the anterolateral segments. Such factors could contribute to an overestimation of the effectiveness of the RLS over LLS. Notably, the reason for open conversion is also significant, as emergency conversion due to an unfavorable intraoperative event may result in worse outcomes than elective conversion for suboptimal intraoperative findings (5). A focused analysis on conversion reasons would be informative.

To address the limitations of retrospective studies, a prospective study design is recommended. Birgin et al. [2024] conducted a single-center, randomized, controlled, single-blinded clinical trial (6) at an academic center with significant expertise in MILS. The study evaluated mean quality of life within 90 days post-surgery and perioperative factors—including operating time, morbidity, blood loss, conversion rate, postoperative recovery, and resection margin status in 80 patients (RLS, n=41; LLS, n=39) between February 21, 2022, and September 18, 2023. Their findings indicated no significant differences between the RLS and LLS groups for these factors.

Despite the limitations, this study holds substantial clinical relevance due to its large sample size. Liver surgeries vary widely in complexity, and the difficulty of each procedure impacts outcome (7). Although prospective studies reduce selection bias, small sample sizes often hinder comparative analysis between robotic and laparoscopic approaches for individual procedures. Robotic surgery is generally considered to benefit complex liver surgeries, such as major hepatectomies (8) or surgeries in the liver’s posterior-superior segments (9). The authors conducted subgroup analyses on minor resections of the anterolateral and posterosuperior segments, and major resections. As anticipated, RLS showed higher TOLS rates than LLS for minor resections of the posterosuperior segments and major resections; however, these differences were not statistically significant. Overall morbidity rates were similar for minor resections, though the RLS group experienced significantly lower than the LLS group. Consistent with previous reports (10), RLS appears effective for complex liver surgeries, and this trend is expected to grow as the RLS technique develops.

Given RLS’s recent adoption, further research is needed to clarify its oncological benefits beyond short-term outcomes. Laparoscopic liver resection is well established (11); therefore it may be difficult to demonstrate significant oncological improvements over laparoscopic surgery despite the surgical acuity of RLS. Nevertheless, the higher R0 resection rate and lower conversion rates observed in the RLS group could suggest improved oncological outcomes, warranting further investigation into its potential for enhancing prognosis. Moreover, RLS’s shorter learning curve (12) and potential for telesurgery (13) present notable advantages over LLS.

One major concern with robotic surgery is its high cost. Koh et al. (14) reported that LLR incurred the lowest total costs compared to open, laparoscopic, and RLS. While robotic liver resection offers notable benefits in terms of mortality and length of stay, these benefits are counterbalanced by the highest total costs. For cost-effective and sustainable surgical practices, determining specific indications for LLS and RLS on a case-by-case basis is essential. Until the cost of robotic surgery is significantly reduced, the use of RLS for simple cases—essentially ‘using a hammer to crack a nut’, should be avoided.

Although RLR is still evolving and relatively new, it has the potential to enhance the quality of MILS. With short-term outcomes stabilizing in advanced medical facilities, surgeons should consider strategies to maximize patient benefits. Sustainable surgical care requires weighing clinical benefits against financial considerations.

Acknowledgments

Funding: None.

Footnote

Provenance and Peer Review: This article was commissioned by the editorial office, HepatoBiliary Surgery and Nutrition. The article did not undergo external peer review.

Conflicts of Interest: Both authors have completed the ICMJE uniform disclosure form (available at https://hbsn.amegroups.com/article/view/10.21037/hbsn-2024-638/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Sijberden JP, Hoogteijling TJ, Aghayan D, et al. Robotic Versus Laparoscopic Liver Resection in Various Settings: An International Multicenter Propensity Score Matched Study of 10.075 Patients. Ann Surg 2024;280:108-17. [Crossref] [PubMed]
2. Görgec B, Zwart M, Nota CL, et al. Implementation and Outcome of Robotic Liver Surgery in the Netherlands: A Nationwide Analysis. Ann Surg 2023;277:e1269-77. [Crossref] [PubMed]
3. Ciria R, Berardi G, Alconchel F, et al. The impact of robotics in liver surgery: A worldwide systematic review and short-term outcomes meta-analysis on 2,728 cases. J Hepatobiliary Pancreat Sci 2022;29:181-97. [Crossref] [PubMed]
4. Görgec B, Benedetti Cacciaguerra A, Lanari J, et al. Assessment of Textbook Outcome in Laparoscopic and Open Liver Surgery. JAMA Surg 2021;156:e212064. [Crossref] [PubMed]
5. Halls MC, Cipriani F, Berardi G, et al. Conversion for Unfavorable Intraoperative Events Results in Significantly Worse Outcomes During Laparoscopic Liver Resection: Lessons Learned From a Multicenter Review of 2861 Cases. Ann Surg 2018;268:1051-7. [Crossref] [PubMed]
6. Birgin E, Heibel M, Hetjens S, et al. Robotic versus laparoscopic hepatectomy for liver malignancies (ROC'N'ROLL): a single-centre, randomised, controlled, single-blinded clinical trial. Lancet Reg Health Eur 2024;43:100972. [Crossref] [PubMed]
7. Ban D, Tanabe M, Ito H, et al. A novel difficulty scoring system for laparoscopic liver resection. J Hepatobiliary Pancreat Sci 2014;21:745-53. [Crossref] [PubMed]
8. Tsung A, Geller DA, Sukato DC, et al. Robotic versus laparoscopic hepatectomy: a matched comparison. Ann Surg 2014;259:549-55. [Crossref] [PubMed]
9. Melstrom LG, Warner SG, Woo Y, et al. Selecting incision-dominant cases for robotic liver resection: towards outpatient hepatectomy with rapid recovery. Hepatobiliary Surg Nutr 2018;7:77-84. [Crossref] [PubMed]
10. Cipriani F, Fiorentini G, Magistri P, et al. Pure laparoscopic versus robotic liver resections: Multicentric propensity score-based analysis with stratification according to difficulty scores. J Hepatobiliary Pancreat Sci 2022;29:1108-23. [Crossref] [PubMed]
11. Fretland ÅA, Dagenborg VJ, Bjørnelv GMW, et al. Laparoscopic Versus Open Resection for Colorectal Liver Metastases: The OSLO-COMET Randomized Controlled Trial. Ann Surg 2018;267:199-207. [Crossref] [PubMed]
12. Chua D, Syn N, Koh YX, et al. Learning curves in minimally invasive hepatectomy: systematic review and meta-regression analysis. Br J Surg 2021;108:351-8. [Crossref] [PubMed]
13. Mohan A, Wara UU, Arshad Shaikh MT, et al. Telesurgery and Robotics: An Improved and Efficient Era. Cureus 2021;13:e14124. [Crossref] [PubMed]
14. Koh YX, Zhao Y, Tan IE, et al. Comparative cost-effectiveness of open, laparoscopic, and robotic liver resection: A systematic review and network meta-analysis. Surgery 2024;176:11-23. [Crossref] [PubMed]