Analysis of surgical approach and tumor distance to margin after liver resection for colorectal liver metastasis

Minimal Invasive Versus Open Surgery for Colorectal Liver Metastases: A Multicenter German StuDoQ|Liver Registry-Based Cohort Analysis in Germany

Objective

To compare the outcome of minimally invasive liver surgery (MILS) to open liver surgery (OLS) for resection of colorectal liver metastases (CRLM) on a nationwide level.

Background

Colorectal cancer is the third most common malignancy worldwide. Up to 50% of all patients with colorectal cancer develop CRLM. MILS represents an attractive alternative to OLS for treatment of CRLM.

Methods

Retrospective cohort study using the prospectively recorded German Quality management registry for liver surgery. Propensity-score matching was performed to account for variance in the extent of resection and patient demographics.

Results

In total, 1037 patients underwent liver resection for CRLM from 2019 to 2021. MILS was performed in 31%. Operative time was significantly longer in MILS (234 vs 222 minutes, P = 0.02) compared with OLS. After MILS, median length of hospital stay (LOS) was significantly shorter (7 vs 10 days; P < 0.001). Despite 76% of major resections being OLS, postoperative complications and 90-day morbidity and mortality did not differ. The Pringle maneuver was more frequently used in MILS (48% vs 40%, P = 0.048). After propensity-score matching for age, body mass index, Eastern Cooperative Oncology Group, and extent of resection, LOS remained shorter in the MILS cohort (6 vs 10 days, P < 0.001) and operative time did not differ significantly (P = 0.2).

Conclusion

MILS is not the standard for resection of CRLM in Germany. Drawbacks, such as a longer operative time remain. However, if technically possible, MILS is a reasonable alternative to OLS for resection of CRLM, with comparable postoperative complications, reduced LOS, and equal oncological radicality.

Robotic hepatectomy: current evidence and future directions

Minimally invasive hepatectomy continues to gain popularity and acceptance for treatment of benign and malignant liver disease. Robotic hepatectomy offers potential advantages over open and conventional laparoscopic approaches. Review of the literature on robotic hepatectomy was performed. Search terms included "robotic hepatectomy" and "minimally invasive hepatectomy." Search was further customized to include articles related to robotic surgical technology. Across many parameters in liver surgery, robotic liver resection appears to have comparable outcomes with respect to laparoscopic resection. The benefits over open resection are largely related to less morbidity and faster recovery times. There is evidence that the robotic approach may have a shorter learning curve and enable more difficult resections to be performed minimally invasively. The robotic platform may have the potential to achieve superior margin status or parenchymal sparing resection in oncologic resections, but numerous obstacles remain. The robotic platform has not been applied to liver surgery to the same extent as either laparoscopic or open surgery. Robotic surgical technology will need to continue developing to deliver on its potential advantages.

International experts consensus guidelines on robotic liver resection in 2023

The robotic liver resection (RLR) has been increasingly applied in recent years and its benefits shown in some aspects owing to the technical advancement of robotic surgical system, however, controversies still exist. Based on the foundation of the previous consensus statement, this new consensus document aimed to update clinical recommendations and provide guidance to improve the outcomes of RLR clinical practice. The guideline steering group and guideline expert group were formed by 29 international experts of liver surgery and evidence-based medicine (EBM). Relevant literature was reviewed and analyzed by the evidence evaluation group. According to the WHO Handbook for Guideline Development, the Guidance Principles of Development and Amendment of the Guidelines for Clinical Diagnosis and Treatment in China 2022, a total of 14 recommendations were generated. Among them were 8 recommendations formulated by the GRADE method, and the remaining 6 recommendations were formulated based on literature review and experts' opinion due to insufficient EBM results. This international experts consensus guideline offered guidance for the safe and effective clinical practice and the research direction of RLR in future.

Survival Study: International Multicentric Minimally Invasive Liver Resection for Colorectal Liver Metastases (SIMMILR-2)

Introduction: Study: International Multicentric Minimally Invasive Liver Resection for Colorectal Liver Metastases (SIMMILR-CRLM) was a propensity score matched (PSM) study that reported short-term outcomes of patients with CRLM who met the Milan criteria and underwent either open (OLR), laparoscopic (LLR) or robotic liver resection (RLR). This study, designated as SIMMILR-2, reports the long-term outcomes from that initial study, now referred to as SIMMILR-1. Methods: Data regarding neoadjuvant chemotherapeutic (NC) and neoadjuvant biological (NB) treatments received were collected, and Kaplan−Meier curves reporting the 5-year overall (OS) and recurrence-free survival (RFS) for OLR, LLR and RLR were created for patients who presented with synchronous lesions only, as there was insufficient follow-up for patients with metachronous lesions. Results: A total of 73% of patients received NC and 38% received NB in the OLR group compared to 70% and 28% in the LLR group, respectively (p = 0.5 and p = 0.08). A total of 82% of patients received NC and 40% received NB in the OLR group compared to 86% and 32% in the RLR group, respectively (p > 0.05). A total of 71% of patients received NC and 53% received NB in the LLR group compared to 71% and 47% in the RLR group, respectively (p > 0.05). OS at 5 years was 34.8% after OLR compared to 37.1% after LLR (p = 0.4), 34.3% after OLR compared to 46.9% after RLR (p = 0.4) and 30.3% after LLR compared to 46.9% after RLR (p = 0.9). RFS at 5 years was 12.1% after OLR compared to 20.7% after LLR (p = 0.6), 33.3% after OLR compared to 26.3% after RLR (p = 0.6) and 22.7% after LLR compared to 34.6% after RLR (p = 0.6). Conclusions: When comparing OLR, LLR and RLR, the OS and RFS were all similar after utilization of the Milan criteria and PSM. Biological agents tended to be utilized more in the OLR group when compared to the LLR group, suggesting that highly aggressive tumors are still managed through an open approach.