Laparoscopic liver resection: indications, limitations, and economic aspects

Impact of complexity in minimally invasive liver surgery on enhanced recovery measures: prospective study

BACKGROUND

Adherence to enhanced recovery after surgery (ERAS) protocols is crucial for successful liver surgery. The aim of this study was to assess the impact of minimally invasive liver surgery complexity on adherence after implementing an ERAS protocol.

METHODS

Between July 2018 and August 2021, a prospective observational study involving minimally invasive liver surgery patients was conducted. Perioperative treatment followed ERAS guidelines and was recorded in the ERAS interactive audit system. Kruskal-Wallis and ANOVA tests were used for analysis, and pairwise comparisons utilized Wilcoxon rank sum and Welch's t-tests, adjusted using Bonferroni correction.

RESULTS

A total of 243 patients were enrolled and categorized into four groups based on the Iwate criteria: low (n = 17), intermediate (n = 81), advanced (n = 74) and expert difficulty (n = 71). Complexity correlated with increased overall and major morbidity rate, as well as longer length of stay (all P < 0.001; standardized mean difference = 0.036, 0.451, 0.543 respectively). Adherence to ERAS measures decreased with higher complexity (P < 0.001). Overall adherence was 65.4%. Medical staff-centred adherence was 79.9%, while patient-centred adherence was 38.9% (P < 0.001). Complexity significantly affected patient-centred adherence (P < 0.001; standardized mean difference (SMD) = 0.420), but not medical staff-centred adherence (P = 0.098; SMD = 0.315). Postoperative phase adherence showed major differences among complexity groups (P < 0.001, SMD = 0.376), with mobilization measures adhered to less in higher complexity cases.

CONCLUSION

The complexity of minimally invasive liver surgery procedures impacts ERAS protocol adherence for each patient. This can be addressed using complexity-adjusted cut-offs and 'gradual adherence' based on the relative proportion of cut-off values achieved.

A Comparison of Laparoscopic Surgery and Open Surgery in Liver Resections: A Single-Center Experience

OBJECTIVE

With the developments in patient management and the increase in surgical experience, the use of laparoscopy in liver resections has become widespread. However, with the consensus meetings and international recommendations, laparoscopic liver resections have been tried to be standardized. We aimed to present this laparoscopic liver resection experience by comparing open and laparoscopic techniques.

MATERIALS AND METHODS

Patients who underwent liver resections between 2015 and 2022 were retrospectively screened and divided into 2 groups as laparoscopic liver resections and patients who underwent liver resection with open surgery. Indications, resection techniques, operative times, length of hospital stay, early hospital mortality, and complications were compared between both groups using statistical methods.

RESULTS

Laparoscopic surgery was performed in 31 (14%) patients, and open surgery was performed in 189 (86%). The mean operation time was 316 ± 168.2 minutes in patients who underwent laparoscopic liver resection. It was 329.4 ± 123.6 in the open surgery group. The length of hospital stay was 11.6 ± 4.9 days in patients who underwent laparoscopic liver resection, while it was 19.7 ± 12.1 days in patients who underwent open surgery. The difference between the length of hospital stay was statistically significant (Mann-Whitney U-test, P=.00). There was no difference between the 2 groups in terms of complications and early mortality.

CONCLUSION

Laparoscopic liver resections are a safe method that can be applied in 3 or less segment resections. As the experience of the surgical team increases, it can be safely applied for major hepatectomies.

Validity of the Institut Mutualiste Montsouris classification system for robotic liver resection

BACKGROUND

The Institut Mutualiste Montsouris (IMM) classification system is one of several widely accepted difficulty scoring systems for laparoscopic liver resections. Nothing is yet known about the applicability of this system for robotic liver resections.

METHODS

We conducted a retrospective review of 359 patients undergoing robotic hepatectomies between 2016 and 2022. Resections were classified into low, intermediate, and high difficulty level. Data were analyzed utilizing ANOVA of repeated measures, 3 x 2 contingency tables, and area under the receiving operating characteristic (AUROC) curves. Data are presented as median (mean ± SD).

RESULTS

Of the 359 patients, 117 were classified as low-difficulty level, 92 as intermediate, and 150 as high. The IMM system correlates well with tumor size (p = 0.002). The IMM system was a strong predictor of intraoperative outcomes including operative duration (p<0.001) and estimated blood loss (EBL) (p<0.001). The IMM system also showed a strong calibration for predicting an open conversion (AUC=0.705) and intraoperative complications (AUC=0.79). In contrast, the IMM system was a poor predictor of postoperative complications, mortality, and readmission.

CONCLUSION

The IMM system provides a strong correlation with intraoperative, but not postoperative outcomes. A dedicated difficulty scoring system should be developed for robotic hepatectomy.

Impact of body mass index on the difficulty and outcomes of laparoscopic left lateral sectionectomy

INTRODUCTION

Currently, the impact of body mass index (BMI) on the outcomes of laparoscopic liver resections (LLR) is poorly defined. This study attempts to evaluate the impact of BMI on the peri-operative outcomes following laparoscopic left lateral sectionectomy (L-LLS).

METHODS

A retrospective analysis of 2183 patients who underwent pure L-LLS at 59 international centers between 2004 and 2021 was performed. Associations between BMI and selected peri-operative outcomes were analyzed using restricted cubic splines.

RESULTS

A BMI of >27kg/m2 was associated with increased in blood loss (Mean difference (MD) 21 mls, 95% CI 5-36), open conversions (Relative risk (RR) 1.13, 95% CI 1.03-1.25), operative time (MD 11 min, 95% CI 6-16), use of Pringles maneuver (RR 1.15, 95% CI 1.06-1.26) and reductions in length of stay (MD -0.2 days, 95% CI -0.3 to -0.1). The magnitude of these differences increased with each unit increase in BMI. However, there was a "U" shaped association between BMI and morbidity with the highest complication rates observed in underweight and obese patients.

CONCLUSION

Increasing BMI resulted in increasing difficulty of L-LLS. Consideration should be given to its incorporation in future difficulty scoring systems in laparoscopic liver resections.

Comparison of Open versus Laparoscopic Approaches in Salvage Hepatectomy for Recurrent Hepatocellular Carcinoma after Radiofrequency Ablation

Background and Objectives: Although radiofrequency ablation (RFA) is widely used as an effective local treatment for hepatocellular carcinoma (HCC), evidence on salvage hepatectomy for local recurrence after RFA is limited. This study aims to compare open and laparoscopic approaches in salvage hepatectomy for recurrent HCC after RFA. Materials and Methods: Among patients who underwent hepatectomy between January 2004 and August 2022 at a single tertiary referral center, 55 patients who underwent salvage hepatectomy for marginal recurrence after RFA were selected. An open approach was used in 23 (41.8%) patients, while 32 (58.2%) patients underwent laparoscopic surgery. Short-term and long-term outcomes were compared between the two groups. Results: Major hepatectomy was more often performed in the open group (9 [39.1%] vs. 4 [12.5%], p = 0.022). Intraoperative blood loss was also greater in the open group (450 (325-750) vs. 300 (200-600), p = 0.034). Operation time (p = 0.144) and postoperative morbidity rates (p = 0.639) were similar, and there was no postoperative mortality in either group. Postoperative hospital stay was significantly longer in the open group compared to the laparoscopy group (8 (6-11) days vs. 5 (4-7) days, p = 0.028). The 1-, 3-, and 5-year disease-free survival rates showed no difference between the two groups (44.6% vs. 62.5%, 16.5% vs. 13.5%, and 8.3% vs. 13.5%, respectively; p = 0.154). The 1-, 3-, and 5-year overall survival rates between the two groups were also similar (85.7% vs. 96.8%, 79.6% vs. 86.0%, and 79.6% vs. 79.4%, respectively; p = 0.480). Conclusions: Laparoscopic salvage hepatectomy shows oncologic outcomes comparable to the open approach with faster postoperative recovery rates. Considering that recurrence rates are high after RFA, the laparoscopic approach should be considered as a first-line option in selected patients.

Propensity score-matched analysis of laparoscopic-assisted and hand-assisted laparoscopic liver resection versus pure laparoscopic liver resection: an international multicenter study

BACKGROUND

Laparoscopic-assisted (LALR) and hand-assisted (HALR) liver resections have been utilized during the early adoption phase by surgeons when transitioning from open surgery to pure LLR. To date, there are limited data reporting on the outcomes of LALR or HALR compared to LLR. The objective was to compare the perioperative outcomes after LALR and HALR versus pure LLR.

METHODS

This is an international multicentric analysis of 6609 patients undergoing minimal-invasive liver resection at 21 centers between 2004 and 2019. Perioperative outcomes were analyzed after propensity score matching (PSM) comparison between LALR and HALR versus LLR.

RESULTS

5279 cases met study criteria of whom 5033 underwent LLR (95.3%), 146 underwent LALR (2.8%) and 100 underwent HALR (1.9%). After 1:4 PSM, LALR was associated with inferior outcomes as evidenced by the longer postoperative stay, higher readmission rate, higher major morbidity rate and higher in-hospital mortality rate. Similarly, 1:6 PSM comparison between HALR and LLR also demonstrated poorer outcomes associated with HALR as demonstrated by the higher open conversion rate and higher blood transfusion rate. All 3 approaches technical variants demonstrated the same oncological radicality (R1 rate).

CONCLUSION

LALR and HALR performed during the learning curve was associated with inferior perioperative outcomes compared to pure LLR.

Laparoscopic versus open repeat hepatectomy for recurrent hepatocellular carcinoma: a systematic review and meta-analysis of propensity score-matched cohort studies

OBJECTIVE

The effectiveness of laparoscopic repeat hepatectomy (LRH) versus open repeat hepatectomy (ORH) on recurrent hepatocellular carcinoma (RHCC) is unclear. We compared the surgical and oncological outcomes of LRH and ORH in patients with RHCC with a meta-analysis of studies based on propensity score-matched cohorts.

METHODS

A literature search was conducted on PubMed, Embase, and Cochrane Library with Medical Subject Headings terms and keywords until 30 September 2022. The quality of eligible studies was evaluated with the Newcastle-Ottawa Scale. Mean difference (MD) with a 95% CI was used for the analysis of continuous variables; odds ratio (OR) with 95% CI was used for binary variables; and hazard ratio with 95% CI was used for survival analysis. A random-effects model was used for meta-analysis.

RESULTS

Five high-quality retrospective studies with 818 patients were included; 409 patients (50%) were treated with LRH and 409 (50%) with ORH. In most surgical outcomes, LRH was superior to ORH: less estimated blood loss, shorter operation time, lower major complication rate, and shorter length of hospital stay (MD=-225.9, 95% CI=[-360.8 to -91.06], P =0.001; MD=66.2, 95% CI=[5.28-127.1], P =0.03; OR=0.18, 95% CI=[0.05-0.57], P =0.004; MD=-6.22, 95% CI=[-9.78 to -2.67], P =0.0006). There were no significant differences in the remaining surgical outcomes: blood transfusion rate and overall complication rate. In oncological outcomes, LRH and ORH were not significantly different in 1-year, 3-year, and 5-year overall survival and disease-free survival.

CONCLUSIONS

For patients with RHCC, most surgical outcomes with LRH were superior to those of ORH, but oncological outcomes with the two operations were similar. LRH may be a preferable option for the treatment of RHCC.

Surgical Approach to Liver Metastases in GEP-NET in a Tertiary Reference Center

Indications for liver resection in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NET) vary from liver resection with curative intent to tumor debulking or tissue sampling for histopathological characterization. With increasing expertise, the number of minimally invasive liver surgeries (MILS) in GEP-NET patients has increased. However, the influence on the oncological outcome has hardly been described. The clinicopathological data of patients who underwent liver resection for hepatic metastases of GEP-NET at the Department of Surgery, Charité—Universitätsmedizin Berlin, were analyzed. Propensity score matching (PSM) was performed to compare MILS with open liver surgery (OLS). In total, 22 patients underwent liver surgery with curative intent, and 30 debulking surgeries were analyzed. Disease-free survival (DFS) was longer than progression-free survival (PFS) (10 vs. 24 months), whereas overall survival (OS) did not differ significantly (p = 0.588). Thirty-nine (75%) liver resections were performed as OLS, and thirteen (25%) as MILS. After PSM, a shorter length of hospital stay was found for the MILS group (14 vs. 10 d, p = 0.034), while neither DFS/PFS nor OS differed significantly. Both curative intended and cytoreductive resection of hepatic GEP-NET metastases achieved excellent outcomes. MILS led to a reduced length of hospital, while preserving a good oncological outcome.

Validation of the Enhanced Recovery after Surgery (ERAS) society recommendations for liver surgery: a prospective, observational study

Background

Twenty-three recommendations were summarized by the Enhanced Recovery After Surgery (ERAS) society for liver surgery. The aim was to validate the protocol especially with regard to adherence and the impact on morbidity.

Methods

Using the ERAS Interactive Audit System (EIAS), ERAS items were evaluated in patients undergoing liver resection. Over a period of 26 months, 304 patients were prospectively enrolled in an observational study (DRKS00017229). Of those, 51 patients (non-ERAS) were enrolled before and 253 patients (ERAS) after the implementation of the ERAS protocol. Perioperative adherence and complications were compared between the two groups.

Results

Overall adherence increased from 45.2% in the non-ERAS group to 62.7% in the ERAS group (P<0.001). This was associated with significant improvements in the preoperative and postoperative phase (P<0.001), rather than in the outpatient and intraoperative phase (both P>0.05). Overall complications decreased from 41.2% (n=21) in the non-ERAS group to 26.5% (n=67) in the ERAS group (P=0.0423), which was mainly due to the reduction of grade 1-2 complications from 17.6% (n=9) to 7.6% (n=19) (P=0.0322). As for patients undergoing open surgery, implementation of ERAS lead to a reduction of overall complications in patients scheduled for minimally invasive liver surgery (MILS) (P=0.036).

Conclusions

Implementation of the ERAS protocol for liver surgery according to the ERAS guidelines of the ERAS Society reduced Clavien-Dindo grade 1-2 complications particularly in patients who underwent MILS. The ERAS guidelines are beneficial for the outcome, while adherence to the various items has not yet been satisfactorily defined.

Perioperative outcomes of robot-assisted versus laparoscopic liver resection for cavernous hemangioma: a propensity score matching study

BACKGROUND

Minimally invasive techniques have increasingly been adopted for liver resection. This study aimed to compare the perioperative outcomes of robot-assisted liver resection (RALR) with laparoscopic liver resection (LLR) for liver cavernous hemangioma and to evaluate the treatment feasibility and safety.

METHODS

A retrospective study of prospectively collected data was conducted on consecutive patients who underwent RALR (n = 43) and LLR (n = 244) for liver cavernous hemangioma between February 2015 and June 2021 at our institution. Patient demographics, tumor characteristics, and intraoperative and postoperative outcomes were analyzed and compared using propensity score matching.

RESULTS

The postoperative hospital stay was significantly shorter (P = 0.016) in the RALR group. There were no significant differences between the two groups in overall operative time, intraoperative blood loss, blood transfusion rates, conversion to open surgery or complication rates. There was no perioperative mortality. Multivariate analysis showed that hemangiomas located in posterosuperior liver segments and those in close proximity to major vascular structures were independent predictors of increased intraoperative blood loss (P = 0.013 and P = 0.001, respectively). For patients with hemangioma in close proximity to major vascular structures, there were no significant differences in perioperative outcomes between the two groups, with the exception that intraoperative blood loss in the RALR group was significantly less than that in the LLR group (350 ml vs. 450 ml, P = 0.044).

CONCLUSIONS

Both RALR and LLR were safe and feasible for treating liver hemangioma in well-selected patients. For patients with liver hemangioma in close proximity to major vascular structures, RALR was better than conventional laparoscopic surgery in reducing intraoperative blood loss.

Pure robotic major hepatectomy with biliary reconstruction for hepatobiliary malignancies: first European results

BACKGROUND

Combined liver and bile duct resection with biliary reconstruction for hepatobiliary malignancies are defined as highly complex surgical procedures. The robotic platform may overcome some major limitations of conventional laparoscopic surgery for these complex cases but its precise role is however still to be defined.

METHODS

In our institution, patients requiring major hepatectomy with biliary reconstruction for malignancies were consecutively selected for minimally invasive robotic surgery from September 2020. All surgeries were undertaken using the da Vinci Xi Surgical System® (Intuitive Surgical, Sunnyvale, CA, USA). Intra-operative technique and postoperative outcome were analyzed.

RESULTS

A total number of 10 patients (3 males and 7 females, median age 72 years) underwent robotic major hepatectomy and bile duct resection for hepatobiliary malignancies between September 2020 and March 2022. The indication for surgery was perihilar cholangiocarcinoma in 5 of 10 patients. Median operative time was 338 min and median blood loss was 110 mL. Postoperative length of stay was between 3 and 16 days (median: 9 days). There was no postoperative 90-day mortality.

CONCLUSIONS

A robotic approach for hepatobiliary malignancies requiring combined major hepatectomy and bile duct resection seems feasible and safe in experienced hands.

Surgical Strategies for Combined Hepatocellular-Cholangiocarcinoma (cHCC-CC)

Combined hepatocellular-cholangiocarcinoma (cHCC-CC) is a tumor entity presenting features of hepatocellular and cholangiocellular epithelial differentiation. Due to the likeness between cHCC-CC, HCC and CC, accurate pretherapeutical diagnosis is challenging and advanced stages are prevalent. Radical oncological surgery is the only curative therapeutical option in patients with cHCC-CC. To reach this goal a profound understanding of this rare liver tumor is crucial. Factors such as clinicopathological characteristics, growth patterns and biological behavior are of central importance. To explore onco-surgical strategies and aspects for complete resection of cHCC-CC and to answer important key questions, an extensive review of the literature was conducted to answer the following questions: What are the best surgical options? Is there a significance for nonanatomical resections? Is there a prognostic value of concomitant lymphadenectomy? What about multimodal concepts in local advanced cHCC-CC? The role of minimally invasive liver surgery (MILS) including the role of robotic liver surgery for cHCC-CC will be discussed. While liver transplantation (LT) is standard for patients with unresectable HCC, the role of LT in cHCC-CC patients is still controversial. How can patients with high risk for early tumor recurrence be identified to avoid aggressive surgical treatment without clinical benefit? The comprehensive understanding of this challenging liver tumor will help to improve future treatment options for these patients.

Robotic Liver Surgery: Technical Advantages Over Laparoscopic Technique Based on Parameters of Surgical Complexity and Perioperative Outcomes

Introduction: In view of the limited availability, our study addresses the issue of optimal case selection for robotic liver surgery over standard laparoscopy offering an in-detail analysis of intra- and postoperative outcomes. Materials and Methods: Clinical and technical data of all consecutive cases of robotic liver surgery of a single high-volume center from 2018 to 2020 were collected prospectively. Second, we performed a retrospective analysis of all laparoscopic liver resections from 2015 to 2020. Parameters of surgical complexity were extracted and descriptive analysis and statistical hypothesis testing were performed to assess parameters of intraoperative and postoperative outcomes. Results: A total of 121 robotic resections were compared with 435 laparoscopic resections. Shorter robotic operating times were shown for segmentectomies of the right liver lobe compared with laparoscopic procedures (P = .003) with an according trend for extended resections. A shorter duration of applied Pringle's maneuver was observed for robotic procedures. This advantage was further enhanced in cases with close proximity of the tumor to major vessels. There were no significant differences in postoperative morbidity and mortality between both groups. Conclusion: Our study offers the first in-detail analysis of intraoperative and postoperative outcomes of robotic liver surgery depending on established parameters of surgical complexity. The results indicate potential technical advantages of robotic technology in liver surgery based on parameters that can be studied before the operation. When evaluating robotic technology, future studies should focus not only at overall postoperative outcomes, but rather at potential technical intraoperative advantages to allow optimal case selection for robotic liver surgery. Clinical Trial Registration Number: DRKS00017229.

Where do we stand in AI for endoscopic image analysis? Deciphering gaps and future directions

Recent developments in deep learning have enabled data-driven algorithms that can reach human-level performance and beyond. The development and deployment of medical image analysis methods have several challenges, including data heterogeneity due to population diversity and different device manufacturers. In addition, more input from experts is required for a reliable method development process. While the exponential growth in clinical imaging data has enabled deep learning to flourish, data heterogeneity, multi-modality, and rare or inconspicuous disease cases still need to be explored. Endoscopy being highly operator-dependent with grim clinical outcomes in some disease cases, reliable and accurate automated system guidance can improve patient care. Most designed methods must be more generalisable to the unseen target data, patient population variability, and variable disease appearances. The paper reviews recent works on endoscopic image analysis with artificial intelligence (AI) and emphasises the current unmatched needs in this field. Finally, it outlines the future directions for clinically relevant complex AI solutions to improve patient outcomes.

Laparoscopic hepatectomy for the treatment of pyogenic liver abscess: A retrospective case-control study

Percutaneous catheter drainage is the first-line treatment for pyogenic liver abscess (PLA). Some patients need hepatectomy because of underling hepatobiliary pathology or unresponsiveness to nonoperative treatment, the traditional method is open hepatectomy (OH). Laparoscopic hepatectomy (LH) for PLA is rarely reported. The purpose of this study is to describe our experience of LH for treating PLA and to compare LH with OH. The medical records of patients who underwent LH for treating PLA were retrospectively analyzed, and the results were compared with those of patients with OH. From January 2015 to December 2021, 61 patients with PLA underwent hepatectomy, and 28 patients who underwent LH (LH group) were compared with 33 patients who underwent OH (OH group). There were no significant differences in the basic data between the 2 groups. Two patients in the LH group were converted to open surgery due to hemorrhage and dense perihepatic adhesions, there was no significant difference between the 2 groups in the operation time (186.2 ± 85.6 vs. 175.9 ± 76.7 minutes, P = .239), Institut Mutualiste Montsouris classification, extent of hepatectomy and drainage tube removal time, however, the blood loss (200.0 ± 100.5 vs. 470.9 ± 120.1 mL, P = .003), numerical rating scale (5.2 ± 1.8 vs. 9.1 ± 1.6, P = .042), the time to resume oral diet (12.3 ± 6.5 vs. 24.6 ± 10.2 hours, P = .005), the ambulant time (20.2 ± 7.3 vs. 40.2 ± 10.8 hours, P = .010), incidence of postoperative complications (14.3% vs.33.3%, P = .002), comprehensive complication index (46.2 vs. 60.6, P = .013), postoperative hospital stay (8.5 ± 7.3 vs. 13.5 ± 10.2 days, P = .025) in the LH group was significantly less than that in the OH group. Wit experience laparoscopic surgeons, treating PLA by LH is safe and feasible and compares favorably with OH.

A novel difficulty scoring system of laparoscopic liver resection for liver tumor

Objectives

To develop a novel difficulty scoring system (NDSS) to predict the surgical difficulty of laparoscopic hepatectomy.

Patients and methods

A total of 138 patients with liver tumors performed liver resection (LLR) between March 2017 to June 2022 were selected from Affiliated Hospital of Jiangnan University and Wujin Hospital Affiliated with Jiangsu University.

Patient demographics, laboratory tests, intraoperative variables, pathological characteristics were assessed. We also assessed the Child Pugh score and the DSS-B score.

Results

Patients were divided into training and testing cohort according to their hospital. Patients in training cohort were divided into high and low difficult groups based on operation time, blood loss and conversion. Higher percentage of patients with malignant liver tumor (87.0% vs. 58.1%; P = 0.003) or history of hepatobiliary surgery (24.1% vs. 7.0%; P = 0.043) in high difficult group than in low difficult group. To improve the difficulty scoring system, we incorporated the history of hepatobiliary surgery and nature of the tumor. A novel difficulty scoring system was established. The results showed that the operation time (P < 0.001), blood loss (P < 0.001), ALT (P < 0.001) and AST (P = 0.001) were associated with the novel difficulty score significantly. Compared with DSS-B, the NDSS has a higher area under the receiver operating characteristic (AUROC) (0.838 vs. 0.814). The nomogram was established according to the NDSS. The AUROCs of the nomogram in training and testing cohort were 0.833 and 0.767. The calibration curves for the probability of adverse event showed optimal agreement between the probability as predicted by the nomogram and the actual probability.

Conclusions

We developed a nomogram with the NDSS that can predict the difficulty of LLR. This system could more accurately reflect the difficulty of surgery and help liver surgeons to make the surgical plan and ensure the safety of the operation.

Current status of robotic surgery for hepato-pancreato-biliary malignancies

INTRODUCTION

Robotic surgery is an emerging aspect of gastrointestinal surgery. Hepato-pancreato-biliary surgery is currently being explored for a broad spectrum of indications, entities, and postoperative outcomes. Noninferiority and financial aspects are the focus of studies. In this review, the impact on oncological therapies is assessed.

AREAS COVERED

An extensive literature review was conducted, and relevant studies and articles and reviews for robotic surgery in the field of hepato-pancreato-biliary surgery were examined. Special attention was given to the oncological aspects of robotic surgery and its possible impact on the therapy of malignant neoplasms.

EXPERT OPINION

Robotic-assisted surgery for oncological indications is promising, in part, an established technique that has already shown its advantages in the last decade, although high-quality studies are missing. Upcoming experience must consider the oncological benefit and putative new indications in a rapidly changing field of anti-neoplastic regimens. Also, robotic surgery may possess the ability to accelerate digitalization and AI-based augmentation in this context.

Four-year experience with more than 1000 cases of total laparoscopic liver resection in a single center

BACKGROUND

Laparoscopic liver resection (LLR) has become a safe surgical procedure that needs additional summarization.

AIM

To review 4 years of total LLR surgeries, exceeding 1000 cases, which were performed at a single center.

METHODS

Patients who underwent LLR at West China Hospital of Sichuan University between January 2015 and December 2018 were identified. Surgical details, including the interventional year, category of liver disease, and malignant liver tumors prognosis, were evaluated. The learning curve for LLR was evaluated using the cumulative sum method. The Kaplan-Meier method was used to perform survival analysis.

RESULTS

Ultimately, 1098 patients were identified. Hepatocellular carcinoma (HCC) was the most common disease that led to the need for LLR at the center (n = 462, 42.08%). The average operation time was 216.94 ± 98.51 min. The conversion rate was 1.82% (20/1098). The complication rate was 9.20% (from grade II to V). The 1-year and 3-year overall survival rates of HCC patients were 89.7% and 81.9%, respectively. The learning curve was grouped into two phases for local resection (cases 1-106 and 107-373), three phases for anatomical segmentectomy (cases 1-44, 45-74 and 75-120), and three phases for hemihepatectomy (cases 1-17, 18-48 and 49-88).

CONCLUSION

LLR may be considered a first-line surgical intervention for liver resection that can be performed safely for a variety of primary, secondary, and recurrent liver tumors and for benign diseases once technical competence is proficiently attained.

Laparoscopic liver resection of segment 8 via a hepatic parenchymal transection-first approach guided by the middle hepatic vein

Background

Pure laparoscopic liver resection (LLR) of segment 8 (S8) is still rarely performed due to the lack of an appropriate surgical approach. This article discusses the technical tips and operation methods for LLR of S8 via a hepatic parenchymal transection-first approach.

Methods

Clinical data of 22 patients who underwent LLR of S8 via a hepatic parenchymal transection-first approach guided by the middle hepatic vein (MHV) in the Second Affiliated Hospital, Third Military Medical University (Army Medical University) from May 2017 to February 2020 were retrospectively analyzed.

Results

The mean age was 51.1 ± 11.6 years; mean operation time, 186.6 ± 18.4 min; median blood loss, 170.0 ml (143.8–205.0 ml); and median length of hospital stay, 8.0 days (7.0–9.0 days). There was no case of open conversion. Pathologic findings revealed all cases of hepatocellular carcinoma (HCC). Pathology showed free surgical margins. Post-operative complications included liver section effusion, pleural effusion, pneumonia, intra-abdomen bleeding and bile leak. All the complications responded well to conservative treatment. No other abnormality was noted during outpatient follow-up examination. All patients survived tumor-free.

Conclusions

LLR of S8 is still quite challenging at present, and it is our goal to design a reasonable procedure with accurate efficacy and high safety. We use hepatic parenchymal transection-first approach guided by the MHV for LLR of S8. This technique overcomes the problem of high technical risk, greatly reduces the surgical difficulty and achieves technological breakthroughs, but there are still many problems worth further exploration.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02289-8.

Future remnant Liver optimization: preoperative assessment, volume augmentation procedures and management of PVE failure

Surgery is the cornerstone treatment for patients with primary or metastatic hepatic tumors. Thanks to surgical and anesthetic technological advances, current indications for liver resections have been significantly expanded to include any patient in whom all disease can be resected with a negative margin (R0) while preserving an adequate future residual liver (FRL). Post-hepatectomy liver failure (PHLF) is still a feared complication following major liver surgery, associated with high morbidity, mortality and cost implications. PHLF is mainly linked to both the size and quality of the FRL. Significant advances have been made in detailed preoperative assessment, to predict and mitigate this complication, even if an ideal methodology has yet to be defined. Several procedures have been described to induce hypertrophy of the FRL when needed. Each technique has its advantages and limitations, and among them portal vein embolization (PVE) is still considered the standard of care. About 20% of patients after PVE fail to undergo the scheduled hepatectomy, and newer secondary procedures, such as segment 4 embolization, ALPPS and HVE, have been proposed as salvage strategies. The aim of this review is to discuss the current modalities available and new perspectives in the optimization of FRL in patients undergoing major liver resection.

Robotic versus open pancreatic surgery: a propensity score-matched cost-effectiveness analysis

Background

Robotic pancreatic surgery (RPS) is associated with high intraoperative costs compared to open pancreatic surgery (OPS). However, it remains unclear whether several advantages of RPS such as reduced surgical trauma and a shorter postoperative recovery time could lead to a reduction in total costs outweighing the intraoperative costs. The study aimed to compare patients undergoing OPS and RPS with regards to cost-effectiveness in a propensity score-matched (PSM) analysis.

Methods

Patients undergoing OPS and RPS between 2017 and 2019 were included in this monocentric, retrospective analysis. The controlling department provided financial data (costs and revenues, net loss/profit). A propensity score-matched analysis was performed or OPS and RPS (matching criteria: age, American society of anesthesiologists (ASA) score, gender, body mass index (BMI), and type of pancreatic resection) with a caliper 0.2.

Results

In total, 272 eligible OPS cases were identified, of which 252 met all inclusion criteria and were thus included in the further analysis. The RPS group contained 92 patients. The matched cohorts contained 41 patients in each group. Length of hospital stay (LOS) was significantly shorter in the RPS group (12 vs. 19 days, p = 0.003). Major postoperative morbidity (Dindo/Clavien ≥ 3a) and 90-day mortality did not differ significantly between OPS and RPS (p > 0.05). Intraoperative costs were significantly higher in the RPS group than in the OPS group (7334€ vs. 5115€, p < 0.001). This was, however, balanced by other financial categories. The overall cost-effectiveness tended to be better when comparing RPS to OPS (net profit—RPS: 57€ vs. OPS: − 2894€, p = 0.328). Binary logistic regression analysis revealed major postoperative complications, longer hospital stay, and ASA scores < 3 were linked to the risk of net loss (i.e., costs > revenue).

Conclusions

Surgical outcomes of RPS were similar to those of OPS. Higher intraoperative costs of RPS are outweighed by advantages in other categories of cost-effectiveness such as decreased lengths of hospital stay.

Complexity-Adjusted Learning Curves for Robotic and Laparoscopic Liver Resection: A Word of Caution

Background

Minimally invasive liver surgery (MILS) has a high variance in the type of resection and complexity, which has been underestimated in learning curve studies in the past. The aim of this work was to evaluate complexity-adjusted learning curves over time for laparoscopic liver resection (LLR) and robotic liver resection (RLR).

Methods

Cumulative sum analysis (CUSUM) and complexity adjustment were performed using the Iwate score for LLR and RLR (n = 647). Lowest point of smoothed data was used to capture the cutoff of the increase in complexity. Data were collected retrospectively at the Department of Surgery of the Charité-Universitätsmedizin Berlin.

Results

A total of 132 RLR and 514 LLR were performed. According to the complexity-adjusted CUSUM analysis, the initial learning phase was reached after 117 for LLR and 93 procedures for RLR, respectively. With increasing experience, the rate of (extended) right hemihepatectomy multiplied from 8.4% to 18.9% for LLR (P = 0.031) and from 21.6% to 58.3% for RLR (P < 0.001). Complication rates remained comparable between both episodes for LLR and RLR (T1 vs T2, P > 0.05). The complexity-adjusted CUSUM analysis demonstrated for blood transfusion, conversion, and operative time an increase during the learning phase (T1), while a steady state was reached in the following (T2).

Conclusions

The learning phase for MILS after adjusting for complexity is about 4 times longer than assumed in previous studies, which should urge caution.

Challenge and future of liver and pancreatic robotic surgery. Analysis of 64 cases in a specialized unit

INTRODUCTION

Robotic surgery has proven effective in certain surgical procedures. However, in liver and pancreatic surgery (HBP) its use is still rare. The initial experience in HBP robotic surgery of a specialized unit of a tertiary hospital is presented.

METHOD

The results of patients undergoing robotic HBP surgery between April 2018 and October 2020 have been prospectively studied. The data analyzed correspond to demographic data, surgical techniques performed, associated morbidity and mortality.

RESULTS

64 patients were operated, corresponding to 35 hepatectomies (major [6.7%], anatomic [52.9%], limited [34.4%], cystectomies [3%] and marsupialization [3%]), 29 pancreatectomies (distal [48.2%], central [6.9%], cephalic [13.8%], enucleations [24.1%], ampullectomies [3.5%] and duodenal resections [3.5%]). In liver surgery the mean operative time was 204.4 min (100-265 min), the median postoperative complications according to the Clavien-Dindo scale was one (1-4), the mean blood losses 166.7 mL (100-300 mL), there was no conversion and the mean postoperative stay was four days (2-14 days). In pancreatic surgery, the mean operative time was 243.8 min (125-460 min), the median of postoperative complications was two (1-4), blood loss of 202.3 mL (100-500 mL) associated to a conversion rate 17.8% and an average stay of seven days (3-23 days).

CONCLUSIONS

Robotic HBP surgery is safe and feasible. It is suggested that its use facilitates parenchymal sparing surgery, access to posterior liver segments and anastomosis in pancreatic reconstruction compared to laparoscopic surgery.

Achievement of textbook outcomes and comparisons with benchmark values after laparoscopic left lateral sectionectomy

Laparoscopic left lateral sectionectomy (LLLS) is considered a standard approach for patients. Textbook outcomes (TOs) with benchmark values have been developed to help centers assess their outcomes of LLLS. The aim of our study was to identify factors associated with achieving TOs after LLLS. This is a retrospective cohort study including 195 patients undergoing LLLS between January 2004 and December 2018. Our outcomes were compared to benchmark values and graded as similar, better, or worse. A TO was achieved in 106 patients (54.4%). The main determinant for achieving a TO was prolonged hospital stay. Year of surgery [P = 0.002; odds ratio (OR) 3.913, 95% confidence interval (CI) 1.666-9.188], American Society of Anesthesiologists (ASA) score (P = 0.015; OR 0.104, 95% CI 0.017-0.650), body mass index (BMI) score (P = 0.075; OR 1.135, 95% CI 0.988-1.304), inflow clamping > 40 min (P = 0.037; OR 0.090, 95% CI 0.009-0.867) and operation time (P = 0.002; OR 0.991, 95% CI 0.985-0.997) were the factors associated with achieving a TO. Our outcomes were similar to the benchmark values for all criteria, except for the transfusion rate (our study vs benchmark values; 6.2% vs 3.8%), which was worse in our patients. We achieved better outcomes with a lower conversion rate (4.6% vs 7.2%), fewer patients requiring massive transfusion (4.1% vs 8.3%), lower rate of prolonged inflow clamping (3.9% vs 6.3%), lower overall complication rate (11.9% vs 19.8%), lower reoperation rate (0% vs 3.4%), and fewer patients with a positive margin (1.5% vs 10.8%). Year of surgery, ASA score, inflow clamping > 40 min and operation time were independently associated with failure to achieve a TO. TOs are useful tools to measure the surgical outcomes and compare surgical performance with benchmark values. TOs also offer a new method to retrospectively compare outcomes.

Augmented Reality and Image-Guided Robotic Liver Surgery

Artificial intelligence makes surgical resection easier and safer, and, at the same time, can improve oncological results. The robotic system fits perfectly with these more or less diffused technologies, and it seems that this benefit is mutual. In liver surgery, robotic systems help surgeons to localize tumors and improve surgical results with well-defined preoperative planning or increased intraoperative detection. Furthermore, they can balance the absence of tactile feedback and help recognize intrahepatic biliary or vascular structures during parenchymal transection. Some of these systems are well known and are already widely diffused in open and laparoscopic hepatectomies, such as indocyanine green fluorescence or ultrasound-guided resections, whereas other tools, such as Augmented Reality, are far from being standardized because of the high complexity and elevated costs. In this paper, we review all the experiences in the literature on the use of artificial intelligence systems in robotic liver resections, describing all their practical applications and their weaknesses.

One-Stage Total Laparoscopic Treatment for Colorectal Cancer With Synchronous Metastasis. Is It Safe and Feasible?

Liver is the main target organ for colorectal cancer (CRC) metastases. It is estimated that ~25% of CRC patients have synchronous metastases at diagnosis, and about 60% of CRC patients will develop metastases during the follow up. Although several teams have performed simultaneous laparoscopic resections (SLR) of liver and colorectal lesions, the feasibility and safety of this approach is still widely debated and few studies on this topic are present in the literature. The purpose of this literature review is to understand the state of the art of SLR and to clarify the potential benefits and limitations of this approach. Several studies have shown that SLR can be performed safely and with short-term outcomes similarly to the separated procedures. Simultaneous laparoscopic colorectal and hepatic resections combine the advantages of one stage surgery with those of laparoscopic surgery. Several reports compared the short-term outcomes of one stage laparoscopic resection with open resections and showed a similar or inferior amount of blood loss, a similar or lower complication rate, and a significant reduction of hospital stay for laparoscopic surgery respect to open surgery but much longer operating times for the laparoscopic technique. Few retrospective studies compared long term outcomes of laparoscopic one stage surgery with the outcomes of open one stage surgery and did not identify any differences about disease free survival and the overall survival. In conclusion, hepatic and colorectal SLR are a safe and effective approach characterized by less intraoperative blood loss, faster recovery of intestinal function, and shorter length of postoperative hospital stay. Moreover, laparoscopic approach is associated to lower rates of surgical complications without significant differences in the long-term outcomes compared to the open surgery.

Safety of intermittent Pringle maneuver during minimally invasive liver resection in patients with hepatocellular carcinoma with and without cirrhosis

Purpose

The aim of this study was to analyze the impact of minimally invasive intermittent Pringle maneuver (IPM) on postoperative outcomes in patients with hepatocellular carcinoma (HCC) and liver cirrhosis.

Methods

In this retrospective cohort study, we evaluated the safety of IPM in patients with HCC who underwent minimally invasive liver resection during five years at our center. Factors influencing the use of IPM were examined in univariate and multivariate regression analysis. Cases with use of IPM (IPM) and those without use of IPM (no IPM) were then compared regarding intraoperative and postoperative outcomes after propensity score matching (PSM) for surgical difficulty.

Results

One hundred fifty-one patients underwent liver resection for HCC at our center and met inclusion criteria. Of these, 73 patients (48%) received IPM with a median duration of 18 min (5–78). One hundred patients (66%) had confirmed liver cirrhosis. In multivariate analysis, patients with large tumors (≥ 3 cm) and difficult tumor locations (segments VII or VIII) were more likely to undergo IPM (OR 1.176, p = 0.043, and OR 3.243, p = 0.001, respectively). After PSM, there were no differences in intraoperative blood transfusion or postoperative complication rates between the IPM and no IPM groups. Neither did we observe any differences in the subgroup analysis for cirrhotic patients. Postoperative serum liver function tests were not affected by the use of IPM.

Conclusions

Based on our findings, we conclude that the use of IPM in minimally invasive liver resection is safe and feasible for patients with HCC, including those with compensated liver cirrhosis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00423-021-02361-z.

Focal nodular hyperplasia associated with a giant hepatocellular adenoma: A case report and review of literature

BACKGROUND

Focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) are well-known benign liver lesions. Surgical treatment is usually chosen for symptomatic patients, lesions more than 5 cm, and uncertainty of diagnosis.

CASE SUMMARY

We described the case of a large liver composite tumor in an asymptomatic 34-year-old female under oral contraceptive for 17-years. The imaging work-out described two components in this liver tumor; measuring 6 cm × 6 cm and 14 cm × 12 cm × 6 cm. The multidisciplinary team suggested surgery for this young woman with an unclear HCA diagnosis. She underwent a laparoscopic left liver lobectomy, with an uneventful postoperative course. Final pathological examination confirmed FNH associated with a large HCA. This manuscript aimed to make a literature review of the current management in this particular situation of large simultaneous benign liver tumors.

CONCLUSION

The simultaneous presence of benign composite liver tumors is rare. This case highlights the management in a multidisciplinary team setting.

Laparoscopic liver resection for primary liver cancers originating in the paracaval portion of the caudate lobe: a preliminary retrospective analysis with 31 patients

Paracaval-originating cancers have been considered a contraindication for laparoscopic liver resection (LLR). This study aimed to explore the safety and feasibility of LLR in the treatment of paracaval-originating cancers. This study included 11 patients who underwent LLR and 20 who underwent open liver resection (OLR) for paracaval-originating cancers between May 2010 and November 2020. The outcomes of the procedures were retrospectively analyzed. There were no cases of perioperative death or conversion to laparotomy. The LLR group had an earlier postoperative feeding time, shorter postoperative hospital stay, and lower total bilirubin levels on the first day after surgery. No significant differences in the incidence of overall postoperative complications were noted between the LLR and OLR groups, but the incidence of grade IIIa complications was significantly higher in the LLR group than in the OLR group. Tumor recurrence occurred in 4 of 11 patients in the LLR group and in 11 of 20 patients in the OLR group. LLR for the treatment of paracaval-originating cancers is safe and feasible in selected patients.

Fluorescence and Ultrasound-guided Laparoscopic Resection of Caudate Lobe for Hepatocellular Carcinoma Located in the Retrocaval Portion

BACKGROUND

Contrast-enhanced intraoperative ultrasonography (CEIOUS) and indocyanine green fluorescence were interesting tool for the visualization of intrahepatic neoplastic nodules. The combinations of the 2 technologies could increase tumor detection and the radicality of resection, allowing the use of a pure laparoscopic approach.

METHODS

The patient was an 81-year-old man with a history of hypertension and treated hepatitis C infection, with a sustained serological response from 2018, previously undergoing laparotomic resection for hepatocellular carcinoma (HCC) in segment 8.During his regular hepatological follow-up, a 25 mm nodule was detected in segment 1, in a retrocaval position. Considering clinical presentation, good liver function (Child A5-MELD 8) and imaging, pure laparoscopic resection of the caudate lobe was performed using fluorescence imaging and CEIOUS navigation guidance.

RESULTS

The operation last for 205 minutes. Blood loss was 100 mL and no blood transfusion was required. She resumed diet on the next day and was discharged 4 days after the operation. Histopathologic examination showed 27 mm HCC with a clear margin. Contrast computed tomography scan performed 3 months after the operation showed no recurrence of the disease.

CONCLUSIONS

A laparoscopic isolated caudate resection for HCC located in the retrocaval portion of the cirrhotic liver seems to be feasible in selected patients and fluorescence imaging and CEIOUS navigation guidance could guarantee a safe and successful surgery.

Safety and feasibility of robotic liver resection after previous abdominal surgeries

BACKGROUND

While minimally invasive liver surgery has been increasingly adopted at least for minor resections, experience with robotic liver surgery is still limited to a few highly specialized centers. Due to the fear of abdominal adhesions, a history of prior surgeries is still used as an argument for open approaches.

METHODS

Clinical data of all consecutive robotic resections at our center, using the da Vinci Xi surgical system, between April, 2018 and December, 2020, were collected and analyzed as part of a prospective, post-marketing observational study (DRKS00017229). Prior abdominal surgeries were specified according to the surgical approach and localization. Baseline and perioperative outcome criteria were compared between patients with prior surgeries (PS) and patients with no prior surgeries (NPS) in univariate and multivariate analyses.

RESULTS

Out of the 126 patients undergoing robotic liver resections, 59% had a history of abdominal surgeries, which were most often colorectal resections (28%) followed by liver resections (20%). Patients with NPS were more likely to undergo robotic liver resection for hepatocellular carcinoma or benign tumors, and to have underlying liver cirrhosis when compared to patients with PS. Other baseline characteristics as well as the extent of resections were similar. Duration of surgery (258 min), conversion rates (6%), and postoperative complications rates (21% Clavien-Dindo ≥ 3) showed no differences between NPS and PS. A subgroup of patients with a history of prior liver surgery showed a longer duration of surgery in univariate analysis. However, this was not confirmed in multivariate analysis which instead revealed tumor entity and liver cirrhosis as independently correlated with duration of surgery.

CONCLUSIONS

We propose robotic liver resection to be safe and feasible, including in patients with prior abdominal surgeries. Each patient should be evaluated for a minimally invasive procedure regardless of a history of previous operations.

[Minimally invasive liver surgery]

Minimally invasive liver surgery is safe and can be performed with results practically equal to those in open surgery. There are different techniques of parenchyma dissection and hemostasis available for the safe performance of minor and major resections, both laparoscopically and robotics based. Due to its technical options robotics-based surgery is a further development of laparoscopy. Expertise in minimally invasive and in liver surgery are essential prerequisites.

Challenge and future of liver and pancreatic robotic surgery. Analysis of 64 cases in a specialized unit

INTRODUCTION

Robotic surgery has proven effective in certain surgical procedures. However, in liver and pancreatic surgery (HBP) its use is still rare. The initial experience in HBP robotic surgery of a specialized unit of a tertiary hospital is presented.

METHOD

The results of patients undergoing robotic HBP surgery between April 2018 and October 2020 have been prospectively studied. The data analyzed correspond to demographic data, surgical techniques performed, associated morbidity and mortality.

RESULTS

64 patients were operated, corresponding to 35 hepatectomies (major [6.7%], anatomic [52.9%], limited [34.4%], cystectomies [3%] and marsupialization [3%]), 29 pancreatectomies (distal [48.2%], central [6.9%], cephalic [13.8%], enucleations [24.1%], ampullectomies [3.5%] and duodenal resections [3.5%]). In liver surgery the mean operative time was 204.4 minutes (100-265 min), the median postoperative complications according to the Clavien-Dindo scale was one (1-4), the mean blood losses 166.7 mL (100-300 mL), there was no conversion and the mean postoperative stay was four days (2-14 days). In pancreatic surgery, the mean operative time was 243.8 minutes (125-460 min), the median of postoperative complications was two (1-4), blood loss of 202.3 mL (100-500 mL) associated to a conversion rate 17.8% and an average stay of seven days (3-23 days).

CONCLUSIONS

Robotic HBP surgery is safe and feasible. It is suggested that its use facilitates parenchymal sparing surgery, access to posterior liver segments and anastomosis in pancreatic reconstruction compared to laparoscopic surgery.

Incidence, Diagnosis and Repair of a Diaphragmatic Hernia Following Hepatic Surgery: A Single Center Analysis of 3107 Consecutive Liver Resections

Diaphragmatic hernia (DH) after a liver resection (LR) is an uncommon but potentially severe complication. In this retrospective study, we aim to share our experience with DH in our hepatic surgery center. We retrospectively analyzed 3107 patients who underwent a liver resection between January 2012 and September 2019. The diagnosis of DH was based on clinical examination and radiological imaging and confirmed by intraoperative findings during surgical repair. Five out of 3107 (0.16%) patients after LR developed DH. Especially, all five DH patients had a major right-sided LR before (n = 716, 0.7%). The mean time interval between initial LR and occurrence of DH was 30 months (range 15 to 44 months). DH exclusively occurred after a right or extended right hepatectomy. Two patients underwent emergency surgery, three were asymptomatic, and DH was diagnosed in follow-up imaging. Three of these five treated patients (60%) developed DH recurrence: two of three (67%) patients after suture repair alone and the only patient after suture repair in combination with an absorbable mesh. The patient who was treated with a composite mesh implant did not show any signs of DH recurrence after 52 months of follow-up. In patients who develop DH after liver surgery, a mesh augmentation with nonresorbable material is generally recommended. In order to diagnose these patients in an early state, we recommend that special attention be paid and a prompt and targeted diagnostic examination of patients with abdominal complaints after right-sided liver resections take place.

Predicting the Risk of Postoperative Complications in Patients Undergoing Minimally Invasive Resection of Primary Liver Tumors

Minimal-invasive techniques are increasingly applied in clinical practice and have contributed towards improving postoperative outcomes. While comparing favorably with open surgery in terms of safety, the occurrence of severe complications remains a grave concern. To date, no objective predictive system has been established to guide clinicians in estimating complication risks as the relative contribution of general patient health, liver function and surgical parameters remain unclear. Here, we perform a single-center analysis of all consecutive patients undergoing laparoscopic liver resection for primary hepatic malignancies since 2010. Among the 210 patients identified, 32 developed major complications. Several independent predictors were identified through a multivariate analysis, defining a preoperative model: diabetes, history of previous hepatectomy, surgical approach, alanine aminotransferase levels and lesion entity. The addition of operative time and whether conversion was required significantly improved predictions and were thus incorporated into the postoperative model. Both models were able to identify patients with major complications with acceptable performance (area under the receiver-operating characteristic curve (AUC) for a preoperative model = 0.77 vs. postoperative model = 0.80). Internal validation was performed and confirmed the discriminatory ability of the models. An easily accessible online tool was deployed in order to estimate probabilities of severe complication without the need for manual calculation.

Minimal-Invasive Versus Open Hepatectomy for Colorectal Liver Metastases: Bicentric Analysis of Postoperative Outcomes and Long-Term Survival Using Propensity Score Matching Analysis

Minimal-invasive hepatectomy (MIH) has been increasingly performed for benign and malignant liver lesions with most promising short-term results. However, the oncological role of MIH in the treatment of patients with colorectal liver metastases (CRLM) needs further investigation. Clinicopathological data of patients who underwent liver resection for CRLM between 2012 and 2017 at the Department of Surgery, Charité-Universitätsmedizin Berlin, and the Inselspital Bern were assessed. Postoperative outcomes und long-term survivals of patients following MIH were compared with those after conventional open hepatectomy (OH) after 1:1 propensity score matching. During the study period, 229 and 91 patients underwent liver resection for CRLM at the Charité Berlin and the Inselspital Bern, respectively. Patients who underwent MIH in one of the two centers (n = 69) were compared with a matched cohort of patients who underwent OH. MIH was associated with lower complication rates (23% vs. 44%, p = 0.011), shorter length of intensive care unit stay (ICU, 1 vs. 2 days, p = 0.043), shorter length of hospital stay (7 vs. 11 days, p < 0.0001), and a reduced need for intraoperative transfusions (12% vs. 25%, p = 0.047) compared to OH. R0 status was achieved in 93% and 75% of patients after MIH and OH, respectively (p = 0.005). After a median follow-up of 31 months, MIH resulted in similar five-year overall survival (OS) rate (56% vs. 48%, p = 0.116) in comparison to OH. MIH for CRLM is associated with lower postoperative morbidity, shorter length of ICU and hospital stay, reduced need for transfusions, and comparable oncologic outcomes compared to the established OH. Our findings suggest that MIH should be considered as the preferred method for the treatment of curatively resectable CRLM.