Are the current difficulty scores for laparoscopic liver surgery telling the whole story? An international survey and recommendations for the future

Impact of neoadjuvant chemotherapy on short-term outcomes after simple and complex minimally invasive minor hepatectomy for colorectal liver metastases: A propensity-score matched and coarsened exact matched study

BACKGROUND

In the last three decades, minimally invasive liver resection has been replacing conventional open approach in liver surgery. More recently, developments in neoadjuvant chemotherapy have led to increased multidisciplinary management of colorectal liver metastases with both medical and surgical treatment modalities. However, the impact of neoadjuvant chemotherapy on the surgical outcomes of minimally invasive liver resections remains poorly understood.

METHODS

A multicenter, international, database of 4998 minimally invasive minor hepatectomy for colorectal liver metastases was used to compare surgical outcomes in patients who received neoadjuvant chemotherapy with surgery alone. To correct for baseline imbalance, propensity score matching, coarsened exact matching and inverse probability treatment weighting were performed.

RESULTS

2546 patients met the inclusion criteria. After propensity score matching there were 759 patients in both groups and 383 patients in both groups after coarsened exact matching. Baseline characteristics were equal after both matching strategies. Neoadjuvant chemotherapy was not associated with statistically significant worse surgical outcomes of minimally invasive minor hepatectomy.

CONCLUSION

Neoadjuvant chemotherapy had no statistically significant impact on short-term surgical outcomes after simple and complex minimally invasive minor hepatectomy for colorectal liver metastases.

Impact of liver cirrhosis, severity of cirrhosis and portal hypertension on the difficulty of laparoscopic and robotic minor liver resections for primary liver malignancies in the anterolateral segments

INTRODUCTION

We performed this study in order to investigate the impact of liver cirrhosis (LC) on the difficulty of minimally invasive liver resection (MILR), focusing on minor resections in anterolateral (AL) segments for primary liver malignancies.

METHODS

This was an international multicenter retrospective study of 3675 patients who underwent MILR across 60 centers from 2004 to 2021.

RESULTS

1312 (35.7%) patients had no cirrhosis, 2118 (57.9%) had Child A cirrhosis and 245 (6.7%) had Child B cirrhosis. After propensity score matching (PSM), patients in Child A cirrhosis group had higher rates of open conversion (p = 0.024), blood loss >500 mls (p = 0.001), blood transfusion (p < 0.001), postoperative morbidity (p = 0.004), and in-hospital mortality (p = 0.041). After coarsened exact matching (CEM), Child A cirrhotic patients had higher open conversion rate (p = 0.05), greater median blood loss (p = 0.014) and increased postoperative morbidity (p = 0.001). Compared to Child A cirrhosis, Child B cirrhosis group had longer postoperative stay (p = 0.001) and greater major morbidity (p = 0.012) after PSM, and higher blood transfusion rates (p = 0.002), longer postoperative stay (p < 0.001), and greater major morbidity (p = 0.006) after CEM. After PSM, patients with portal hypertension experienced higher rates of blood loss >500 mls (p = 0.003) and intraoperative blood transfusion (p = 0.025).

CONCLUSION

The presence and severity of LC affect and compound the difficulty of MILR for minor resections in the AL segments. These factors should be considered for inclusion into future difficulty scoring systems for MILR.

Impact of liver cirrhosis and portal hypertension on minimally invasive limited liver resection for primary liver malignancies in the posterosuperior segments: An international multicenter study

INTRODUCTION

To assess the impact of cirrhosis and portal hypertension (PHT) on technical difficulty and outcomes of minimally invasive liver resection (MILR) in the posterosuperior segments.

METHODS

This is a post-hoc analysis of patients with primary malignancy who underwent laparoscopic and robotic wedge resection and segmentectomy in the posterosuperior segments between 2004 and 2019 in 60 centers. Surrogates of difficulty (i.e, open conversion rate, operation time, blood loss, blood transfusion, and use of the Pringle maneuver) and outcomes were compared before and after propensity-score matching (PSM) and coarsened exact matching (CEM).

RESULTS

Of the 1954 patients studied, 1290 (66%) had cirrhosis. Among the cirrhotic patients, 310 (24%) had PHT. After PSM, patients with cirrhosis had higher intraoperative blood transfusion (14% vs. 9.3%; p = 0.027) and overall morbidity rates (20% vs. 14.5%; p = 0.023) than those without cirrhosis. After coarsened exact matching (CEM), patients with cirrhosis tended to have higher intraoperative blood transfusion rate (12.1% vs. 6.7%; p = 0.059) and have higher overall morbidity rate (22.8% vs. 12.5%; p = 0.007) than those without cirrhosis. After PSM, Pringle maneuver was more frequently applied in cirrhotic patients with PHT (62.2% vs. 52.4%; p = 0.045) than those without PHT.

CONCLUSION

MILR in the posterosuperior segments in cirrhotic patients is associated with higher intraoperative blood transfusion and postoperative morbidity. This parameter should be utilized in the difficulty assessment of MILR.

Impact of liver cirrhosis, the severity of cirrhosis, and portal hypertension on the outcomes of minimally invasive left lateral sectionectomies for primary liver malignancies

BACKGROUND

The impact of cirrhosis and portal hypertension on perioperative outcomes of minimally invasive left lateral sectionectomies remains unclear. We aimed to compare the perioperative outcomes between patients with preserved and compromised liver function (noncirrhotics versus Child-Pugh A) when undergoing minimally invasive left lateral sectionectomies. In addition, we aimed to determine if the extent of cirrhosis (Child-Pugh A versus B) and the presence of portal hypertension had a significant impact on perioperative outcomes.

METHODS

This was an international multicenter retrospective analysis of 1,526 patients who underwent minimally invasive left lateral sectionectomies for primary liver malignancies at 60 centers worldwide between 2004 and 2021. In the study, 1,370 patients met the inclusion criteria and formed the final study group. Baseline clinicopathological characteristics and perioperative outcomes of these patients were compared. To minimize confounding factors, 1:1 propensity score matching and coarsened exact matching were performed.

RESULTS

The study group comprised 559, 753, and 58 patients who did not have cirrhosis, Child-Pugh A, and Child-Pugh B cirrhosis, respectively. Six-hundred and thirty patients with cirrhosis had portal hypertension, and 170 did not. After propensity score matching and coarsened exact matching, Child-Pugh A patients with cirrhosis undergoing minimally invasive left lateral sectionectomies had longer operative time, higher intraoperative blood loss, higher transfusion rate, and longer hospital stay than patients without cirrhosis. The extent of cirrhosis did not significantly impact perioperative outcomes except for a longer duration of hospital stay.

CONCLUSION

Liver cirrhosis adversely affected the intraoperative technical difficulty and perioperative outcomes of minimally invasive left lateral sectionectomies.

Analysis of Clinical Outcomes After Robotic Hepatectomy Applying the Western-Model Southampton Laparoscopic Difficulty Scoring System. An Experience From a Tertiary US Hepatobiliary Center

BACKGROUND

Identification of resections with high risk of intraoperative complications is critical in guiding case selection for minimally invasive liver surgery. Several Japanese and European difficulty scoring systems have been proposed for laparoscopic liver surgery. However, the applicability of these systems for robotic liver resections has not been fully investigated. This study considers the Southampton system and examines its validity when applied to robotic hepatectomies.

METHODS

We undertook a retrospective review of 372 patients who underwent robotic hepatectomies for various indications between 2013 and 2022. Of these patients, 63 operations were classified as low risk, 91 as moderate risk, 198 as high risk and 20 as extremely high risk based on Southampton criteria. Patient outcomes were compared by utilizing an ANOVA of repeated measures. Data are presented as median (mean ± SD).

RESULTS

The Southampton difficulty scoring system was a strong predictor of intraoperative variables including tumor size, operative duration, estimated blood loss (EBL), and incidence of major vs minor resection (all P < .0001). In contrast, the Southampton system was a weaker predictor of postoperative outcomes including 30-day mortality (P = .15), length of stay (P = .13), and readmissions within 30 days (P = .38).

CONCLUSION

The Southampton difficulty scoring system is a valid system for classifying robotic liver resections and is a strong predictor of intraoperative outcomes. However, the system was found to be a weaker predictor of postoperative outcomes. This finding may suggest the need for proposal of a new difficulty scoring system for robotic hepatectomies.

Impact of neoadjuvant chemotherapy on the difficulty and outcomes of laparoscopic and robotic major liver resections for colorectal liver metastases: A propensity-score and coarsened exact-matched controlled study

BACKGROUND

Minimal invasive liver resections are a safe alternative to open surgery. Different scoring systems considering different risks factors have been developed to predict the risks associated with these procedures, especially challenging major liver resections (MLR). However, the impact of neoadjuvant chemotherapy (NAT) on the difficulty of minimally invasive MLRs remains poorly investigated.

METHODS

Patients who underwent laparoscopic and robotic MLRs for colorectal liver metastases (CRLM) performed across 57 centers between January 2005 to December 2021 were included in this analysis. Patients who did or did not receive NAT were matched based on 1:1 coarsened exact and 1:2 propensity-score matching. Pre- and post-matching comparisons were performed.

RESULTS

In total, the data of 5189 patients were reviewed. Of these, 1411 procedures were performed for CRLM, and 1061 cases met the inclusion criteria. After excluding 27 cases with missing data on NAT, 1034 patients (NAT: n = 641; non-NAT: n = 393) were included. Before matching, baseline characteristics were vastly different. Before matching, the morbidity rate was significantly higher in the NAT-group (33.2% vs. 27.2%, p-value = 0.043). No significant differences were seen in perioperative outcomes after the coarsened exact matching. After the propensity-score matching, statistically significant higher blood loss (mean, 300 (SD 128-596) vs. 250 (SD 100-400) ml, p-value = 0.047) but shorter hospital stay (mean, 6 [4-8] vs. 6 [5-9] days, p-value = 0.043) were found in the NAT-group.

CONCLUSION

The current study demonstrated that NAT had minimal impact on the difficulty and outcomes of minimally-invasive MLR for CRLM.

Does CPT Modifier 22 Appropriately Reflect a Difficult Pancreaticoduodenectomy? Retrospective Analysis of Operative Outcomes and Cost

BACKGROUND

CPT coding allows addition of a 2-digit modifier code to denote particularly difficult procedures necessitating additional reimbursement, called the modifier 22. The use of modifier 22 in relation to pancreatic surgery and outcomes, specifically pancreaticoduodenectomy (PD), has not been explored.

STUDY DESIGN

All PDs performed from 2010 to 2019 at a quaternary healthcare system were analyzed for differences in preoperative characteristics, outcomes, and cost based on the use of modifier 22. Adjusted logistic regression analysis was used to identify factors predictive of modifier 22 use.

RESULTS

A total of 1,284 patients underwent PD between 2010 and 2019; 1,173 with complete data were included, of which 320 (27.3%) were coded with modifier 22. Patients coded with modifier 22 demonstrated a significantly longer duration of surgery (365.9 ± 168.4 vs 227 ± 97.1; p < 0.001). They also incurred significantly higher cost of index admission ($37,446 ± 34,187 vs $28,279 ± 27,980; p = 0.002). An adjusted multivariable analysis (specifically adjusted for surgeon variation) revealed duration of surgery (p < 0.001), neoadjuvant chemotherapy (p = 0.039), class II obesity (p = 0.019), and chronic pancreatitis (p = 0.005) to be predictive of modifier 22 use.

CONCLUSIONS

Despite the subjective nature of this CPT modifier, modifier 22 is an appropriate marker of intraoperative difficulty. Preoperative and intraoperative characteristics that lead to its addition may be used to further delineate difficult PDs.

The difficulty grade of laparoscopic hepatectomy for hepatocellular carcinoma correlates with long-term outcomes

The tremendous development of laparoscopic hepatectomy helps to relieve the difficulties encountered during open hepatectomy. Therefore, a difficulty scoring system was produced to assess the difficulty grade of laparoscopic hepatectomy. The aim of this study was to explore whether the IWATE-DSS is comparable to the long-term outcomes of LH for hepatocellular carcinoma. Clinical data from all consecutive patients who underwent laparoscopic hepatectomy for hepatocellular carcinoma at the Sir Run Run Shaw Hospital, Hangzhou, were prospectively collected and reviewed. The difficulty level of the operations was graded using the IWATE-DSS. The perioperative and postoperative outcomes of laparoscopic hepatectomy were compared at each difficulty level. A total of 300 patients underwent laparoscopic hepatectomy for HCC during the study period. The perioperative and postoperative outcomes were significantly different between the groups according to the IWATE-DSS. There were significant differences in both the intraoperative (bleeding control p = 0.000; surgical time p = 0.000; estimated blood loss p = 0.033) and postoperative variables (postoperative hospital stay p = 0.005) among these four groups. The 5-year disease-free survival decreased significantly along with the LH difficulty score (p = 0.000). The 5-year overall survival also decreased significantly along with the LH difficulty score (p = 0.000). IWATE-DSS was significantly correlated with short- and long-term outcomes in patients who underwent laparoscopic hepatectomy for HCC.

Systematic review and meta-analysis of difficulty scoring systems for laparoscopic and robotic liver resections

INTRODUCTION

The ability to stratify the difficulty of minimally invasive liver resection (MILR) allows surgeons at different phases of the learning curve to tackle cases of appropriate difficulty safely. Several difficulty scoring systems (DSS) have been formulated which attempt to accurately stratify this difficulty. The present study aims to review the literature pertaining to the existing DSS for MILR.

METHODS

We performed a systematic review and metanalysis of the literature reporting on the formulation, supporting data, and comparison of DSS for MILR.

RESULTS

A total of 11 studies were identified which reported on the formulation of unique DSS for MILR. Five of these (Ban, Iwate, Hasegawa, Institut Mutaliste Montsouris [IMM], and Southampton DSS) were externally validated and shown to predict difficulty of MILR via a range of outcome measures. The Ban DSS was supported by pooled data from 10 studies (9 LLR, 1 RLR), Iwate by 10 studies (8 LLR, 2 RLR), Hasegawa by four studies (all LLR), IMM by eight studies (all LLR), and Southampton by five studies (all LLR). There was no clear superior DSS.

CONCLUSION

The existing DSS were all effective in predicting difficulty of MILR. Present studies comparing between DSS have not established a clear superior system, and the five main DSS have been found to be predictive of difficulty in LLR and two of these in RLR.

A machine learning analysis of difficulty scoring systems for laparoscopic liver surgery

INTRODUCTION

In the last decade, several difficulty scoring systems (DSS) have been proposed to predict technical difficulty in laparoscopic liver resections (LLR). The present study aimed to investigate the ability of four DSS for LLR to predict operative, short-term, and textbook outcomes.

METHODS

Patients who underwent LLR at a single tertiary referral center from January 2014 to June 2020 were included in the present study. Four DSS for LLR (Halls, Hasegawa, Kawaguchi, and Iwate) were investigated to test their ability to predict operative and postoperative complications. Machine learning algorithms were used to identify the most important DSS associated with operative and short-term outcomes.

RESULTS

A total of 346 patients were included in the analysis, 28 (8.1%) patients were converted to open surgery. A total of 13 patients (3.7%) had severe (Clavien-Dindo ≥ 3) complications; the incidence of prolonged length of stay (> 5 days) was 39.3% (n = 136). No patients died within 90 days after the surgery. According to Halls, Hasegawa, Kawaguchi, and Iwate scores, 65 (18.8%), 59 (17.1%), 57 (16.5%), and 112 (32.4%) patients underwent high difficulty LLR, respectively. In accordance with a random forest algorithm, the Kawaguchi DSS predicted prolonged length of stay, high blood loss, and conversions and was the best performing DSS in predicting postoperative outcomes. Iwate DSS was the most important variable associated with operative time, while Halls score was the most important DSS predicting textbook outcomes. No one of the DSS investigated was associated with the occurrence of complication.

CONCLUSIONS

According to our results DDS are significantly related to surgical complexity and short-term outcomes, Kawaguchi and Iwate DSS showed the best performance in predicting operative outcomes, while Halls score was the most important variable in predicting textbook outcome. Interestingly, none of the DSS showed any correlation with or importance in predicting overall and severe postoperative complications.

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.

Short-term Outcomes and Difficulty of Repeat Laparoscopic Liver Resection

Objectives

To investigate the feasibility of repeat laparoscopic liver resection (Rep-LLR), including repeat anatomical resection (Rep-AR), as compared to initial-LLR (Ini-LLR).

Background

The indications of LLR have expanded to treatment of recurrent liver tumors. However, the feasibility of Rep-LLR, including Rep-AR, has not yet been adequately assessed.

Methods

Data of 297 patients who had undergone LLR were reviewed. Among the 297 patients, 235 (AR: 168) had undergone Ini-LLR and 62 (AR: 27) had undergone Rep-LLR, and the surgical outcomes were compared between the groups. In addition, multivariate analysis was performed to identify predictors of the difficulty of Rep-LLR based on the operation time and volume of blood loss.

Results

Of the 62 patients who had undergone Rep-LLR, 44, 14, and 4 had undergone second, third, and fourth repeat LRs, respectively. No significant intergroup differences were observed in regard to the operation time, blood loss, conversion rate to open surgery, postoperative morbidity, or postoperative hospital stay. However, the proportion of patients in whom the Pringle maneuver was used was significantly lower in the Rep-LLR group than in the Ini-LLR group. Multivariate analysis identified surgical procedure ≥sectionectomy at the initial/previous LR and an IWATE difficulty score of ≥6 as being independent predictors of the difficulty of Rep-LLR. Use of adhesion barriers at the initial/previous LR was associated with a decreased risk of failure to perform the Pringle maneuver during Rep-LLR.

Conclusions

Rep-LLR can offer outcomes comparable to those of Ini-LLR over the short term.

What Is the Current Role and What Are the Prospects of the Robotic Approach in Liver Surgery?

Simple Summary

Robotic liver surgery is being applied with increasing frequency. Comparable, and in specific settings superior, perioperative outcomes compared to laparoscopic liver surgery have been reported. In its current form, the most commonly mentioned advantage of robotic surgery is improved dexterity. Important obstacles to its wider implementation in daily clinical practice are the associated costs, technical difficulties, and a scarce amount of evidence. Robotic liver surgery will likely continue to evolve in parallel with technological developments that enhance the robots’ abilities.

Abstract

In parallel with the historical development of minimally invasive surgery, the laparoscopic and robotic approaches are now frequently utilized to perform major abdominal surgical procedures. Nevertheless, the role of the robotic approach in liver surgery is still controversial, and a standardized, safe technique has not been defined yet. This review aims to summarize the currently available evidence and prospects of robotic liver surgery. Minimally invasive liver surgery has been extensively associated with benefits, in terms of less blood loss, and lower complication rates, including liver-specific complications such as clinically relevant bile leakage and post hepatectomy liver failure, when compared to open liver surgery. Furthermore, comparable R0 resection rates to open liver surgery have been reported, thus, demonstrating the safety and oncological efficiency of the minimally invasive approach. However, whether robotic liver surgery has merits over laparoscopic liver surgery is still a matter of debate. In the current literature, robotic liver surgery has mainly been associated with non-inferior outcomes compared to laparoscopy, although it is suggested that the robotic approach has a shorter learning curve, lower conversion rates, and less intraoperative blood loss. Robotic surgical systems offer a more realistic image with integrated 3D systems. In addition, the improved dexterity offered by robotic surgical systems can lead to improved intra and postoperative outcomes. In the future, integrated and improved haptic feedback mechanisms, artificial intelligence, and the introduction of more liver-specific dissectors will likely be implemented, further enhancing the robots’ abilities.

Laparoscopic versus open resections in the posterosuperior liver segments within an enhanced recovery programme (ORANGE Segments): study protocol for a multicentre randomised controlled trial

BACKGROUND

A shift towards parenchymal-sparing liver resections in open and laparoscopic surgery emerged in the last few years. Laparoscopic liver resection is technically feasible and safe, and consensus guidelines acknowledge the laparoscopic approach in the posterosuperior segments. Lesions situated in these segments are considered the most challenging for the laparoscopic approach. The aim of this trial is to compare the postoperative time to functional recovery, complications, oncological safety, quality of life, survival and costs after laparoscopic versus open parenchymal-sparing liver resections in the posterosuperior liver segments within an enhanced recovery setting.

METHODS

The ORANGE Segments trial is an international multicentre randomised controlled superiority trial conducted in centres experienced in laparoscopic liver resection. Eligible patients for minor resections in the posterosuperior segments will be randomised in a 1:1 ratio to undergo laparoscopic or open resections in an enhanced recovery setting. Patients and ward personnel are blinded to the treatment allocation until postoperative day 4 using a large abdominal dressing. The primary endpoint is time to functional recovery. Secondary endpoints include intraoperative outcomes, length of stay, resection margin, postoperative complications, 90-day mortality, time to adjuvant chemotherapy initiation, quality of life and overall survival. Laparoscopic liver surgery of the posterosuperior segments is hypothesised to reduce time to functional recovery by 2 days in comparison with open surgery. With a power of 80% and alpha of 0.04 to adjust for interim analysis halfway the trial, a total of 250 patients are required to be randomised.

DISCUSSION

The ORANGE Segments trial is the first multicentre international randomised controlled study to compare short- and long-term surgical and oncological outcomes of laparoscopic and open resections in the posterosuperior segments within an enhanced recovery programme.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03270917 . Registered on September 1, 2017. Before start of inclusion.

PROTOCOL VERSION

version 12, May 9, 2017.

Location of Hemangioma is an Individual Risk Factor for Massive Bleeding in Laparoscopic Hepatectomy

Background and Objectives:

The scope of laparoscopic surgery has expanded to encompass hepatic resections, specifically hepatic hemangioma. The most serious intraoperative complication is bleeding, often requiring laparotomy. Because risk factors associated with such massive blood loss have not been well evaluated, the intent of this retrospective study was to analyze these risk factors associated with laparoscopic resection of hepatic hemangiomas.

Methods:

From June 1, 2011 to January 31, 2021, 140 consecutive patients underwent laparoscopic surgery for hepatic hemangioma in our hospital. According to quantity of intraoperative blood loss, they were divided into massive (≥ 800 ml) and minor blood loss (< 800 ml) groups. Perioperative data were analyzed by univariate and multivariate analyses with logistic regression to identify the risk factors for potential massive blood loss during laparoscopic resection.

Results:

There were 24 and 116 patients in the massive and minor blood loss groups, respectively. Of four risk factors significantly associated with massive blood loss by univariate logistic regression analysis (location of hemangioma in the liver, postcaval or hepatic venous compression, hilar compression, and body mass index exceeding 28) the multifactorial logistic model identified only location in the liver of the hemangioma as statistically (P = 0.012) associated with intraoperative massive blood loss.

Conclusions:

Location of the hepatic hemangioma was the single statistically significant risk factor for massive blood loss during laparoscopic surgery for hepatic hemangioma. Of particular importance, location in Couinaud liver segments I, IVa, VII, and VIII necessitates precautions to mitigate the risk of massive blood loss.

A scoring system to predict surgical difficulty in minimally invasive surgery for gastric submucosal tumors

BACKGROUND

Various minimally invasive surgery (MIS) procedures are used for gastric submucosal tumors (SMTs), and their technical difficulties vary. Preoperative understanding of difficulties is crucial; however, objective indicators are lacking.

METHODS

Gastric SMTs requiring MIS (n = 36) were retrospectively analyzed. Preoperative factors were evaluated using a multivariate linear regression analysis. A scoring system was then constructed, and its feasibility was evaluated.

RESULTS

Three factors were identified and scored based on the weighted contribution for predicting surgical time: tumor location (cardia, score of "2"; posterior wall of fundus, "1"); tumor size (greater than 4 cm, "1"); and tumor growth appearance (intraluminal, "1"). The summed scores could stratify the surgical time stepwise in each score, and patients who scored higher than 3 had larger intraoperative blood loss and a longer hospital stay.

CONCLUSION

Our scoring system predicted surgical difficulties and may, therefore, be useful in selecting appropriate surgical approaches for gastric SMTs.

Evaluation of the Iwate Model for Predicting the Difficulty of Laparoscopic Liver Resection: Does Tumor Size Matter?

BACKGROUND

This study aimed to externally validate the Iwate scoring model and its prognostic value for predicting the risks of intra- and postoperative complications of laparoscopic liver resection.

METHODS

Consecutive patients who underwent pure laparoscopic liver resection between 2008 and 2019 at a single tertiary center were included. The Iwate scores were calculated according to the original proposition (four difficulty levels based on six indices). Intra- and postoperative complications were compared across difficulty levels. Fitting the obtained data to the cumulative density function of the Weibull distribution and a linear function provided the mean risk curves for intra- and postoperative complications, respectively.

RESULTS

The difficulty levels of 142 laparoscopic liver resections were scored as low, intermediate, advanced, and expert level in 41 (28.9%), 53 (37.3%), 32 (22.5%), and 16 (11.3%) patients, respectively. Intraoperative complications were detected in 26 (18.3%) patients and its rates (2.4%, 7.5%, 34.3%, and 62.5%) increased gradually with statistically significant values among difficulty levels (P ˂ 0.001). Major postoperative complications occurred in 21 (14.8%) patients and its rates (4.8%, 5.6%, 28.1%, 43.7%; P ˂ 0.001) showed the same trend as for intraoperative complications. Then, the mean risk curves of both complications were obtained. Due to outliers, a new threshold for a tumor size index was proposed at 38 mm. The repeated analysis showed improved results.

CONCLUSIONS

The Iwate scoring model predicts the probability of complications across difficulty levels. Our proposed tumor size threshold (38 mm) improves the quality of the prediction. The model is upgraded by a probability of complications for every difficulty score.

Validation of the IWATE criteria as a laparoscopic liver resection difficulty score in a single North American cohort

BACKGROUND

Laparoscopic liver resection (LLR) involves a difficult learning curve, for which multiple difficulty scores have been proposed to assist with safe adaptation. The IWATE Criteria is a 4-level difficulty score shown to correlate with conversion to open surgery, estimated blood loss (EBL), and operative time in Japanese and French cohorts. We set out to validate the IWATE Criteria in a North American cohort, describe the evolution of our LLR program, and analyze the IWATE Criteria's ability to predict conversion to open surgery.

METHODS

Patients that underwent LLR between January 2006 and December 2019 were selected from a prospectively maintained database. Difficulty outcomes, including conversion to open surgery, EBL, operative time, and post-operative complications were analyzed according to IWATE difficulty level, both overall and between chronological eras. The IWATE Criteria's ability to predict conversion to open surgery was assessed with a receiver operating characteristic (ROC) analysis.

RESULTS

A total of 426 patients met inclusion criteria. Operative time, EBL, and conversion to open surgery increased in concordance with low to advanced IWATE difficulty. ROC analysis for conversion to open surgery demonstrated an overall area under the curve (AUC) of 0.694. Predictive performance was superior during the first two eras, with AUCs of 0.771 and 0.775; predictive value decreased as the LLR program gained experience, with AUCs of 0.708 and 0.551 for eras three and four.

CONCLUSIONS

This study validated the IWATE Criteria in a North American population distinct from previous Japanese and French cohorts, based on its correlation with operative time, EBL, and conversion to open surgery. The IWATE Criteria may be of utility for identification of LLR cases appropriate for surgeon experience, as well as determination of laparoscopic feasibility. Interval difficulty score recalibration may be warranted as surgeon perception of difficulty evolves.

Hand-assisted Laparoscopic Surgery for Colorectal Liver Metastasis: Analysis of Short-term and Long-term Results

BACKGROUND

There is scant data regarding the outcomes of hand-assisted laparoscopic surgery (HALS) for colorectal liver metastasis (CRLM). The aim of this study is to report our experience and analyze the short-term and long-term results.

MATERIALS AND METHODS

Retrospective study of patients undergoing HALS for CRLM in 2 university affiliated medical centers.

RESULTS

Two hundred and thirty-eight liver procedures were performed on 145 patients including 205 parenchymal sparing resections and 33 anatomic resections. The median number of metastases was 1 (range: 1 to 8), 38 patients (26.2%) had 3 or more metastases, and 41 patients (28.3 had a bi-lobar disease. The tumor size was 20 (2 to 90) mm, and 52 patients (36.6%) had a tumor larger than 30 mm. Nighty-nine patients (67.8%) received neoadjuvant chemotherapy. In 8 patients (5.5%) the laparoscopic liver resection was combined with ablation, and 16 patients (11%) underwent a synchronous resection of colorectal cancer. The median operative time, blood loss during surgery, and postoperative hospital stay were 163 minutes, 300 mL, and 4 days, respectively. The median modified Iwate complexity score was 4 (0 to 10) and the conversion rate to open surgery was 5.5%. The overall and major complication rates were 23.8% and 3.6%, respectively. The mortality rate was 0.7%. R0 resections were achieved in 91% of patients. Median overall survival for all the cohort (intend to treat) was 59 months, and the 8- and 10-year overall survival rates were 47.3% and 24.9%, respectively.

CONCLUSIONS

This study shows that HALS is a safe and efficacious treatment for selected patients with CRLM.

[Evidence of minimally invasive oncological surgery of the liver]

BACKGROUND

The evidence for minimally invasive surgery (MIS) of the liver has significantly increased with the increasing number of publications on this topic in recent years; however, this technique has not yet gained broad acceptance among surgeons.

OBJECTIVE

Analysis and presentation of the current literature on MIS of the liver.

MATERIAL UND METHODS

Structured PubMed literature search and analysis.

RESULTS

According to the literature, MIS and open liver surgery are equivalent regarding the oncological quality. In addition to parenchyma-preserving resections, major hepatectomies (e.g. hemihepatectomy and sectorectomy), two-stage concepts and re-resections have increasingly been reported. The MIS of the liver is associated with less blood loss and other immunological advantages in addition to a shorter hospital stay. The highest level of evidence has been achieved for colorectal liver metastases for which a systematic review even revealed a survival benefit for patients undergoing MIS surgery. From an oncological perspective, laparoscopic and robotic liver surgery are considered to be equivalent.

CONCLUSION

According to the current literature MIS of the liver is recommended for the resection of colorectal liver metastases and hepatocellular carcinoma.

Surgical outcomes of 118 complex laparoscopic liver resections: a single- center experience

BACKGROUND

Indications for laparoscopic liver resection (LLR) are continuously expanding. The Japanese Society of Hepato-Biliary-Pancreatic Surgery defines highly difficult hepatectomy as a procedure involving one or more sections (except for left lateral sectionectomy) or anatomical segmentectomy. This study aimed to assess the outcomes of complex LLR procedures and compare their technical difficulties, about which only a little is known to date.

METHODS

We performed a retrospective review of the operative outcomes of 118 consecutive patients who underwent pure laparoscopic complex hepatectomy. The surgical outcomes, including operative times, blood loss amounts, and postoperative morbidity rates, were compared among complex LLR procedures.

RESULTS

The overall median operative time was 280 minutes, and the median intraoperative blood loss was 86 mL. Two patients required conversion to open laparotomy (1.7%). The postoperative major morbidity rate was 11.0% Posterosuperior segmentectomy, right hemihepatectomy, and anterior sectionectomy required the longest operative times. Anterior and posterior sectionectomy resulted in the highest blood loss, and right hemihepatectomy and anterior sectionectomy resulted in the most complications.

CONCLUSIONS

The surgical difficulties associated with complex LLR procedures vary. It is critical to recognize the specific risks and cautionary points to ensure patient safety and provide proper systemic training to surgeons.

Impact of liver cirrhosis on the difficulty of minimally-invasive liver resections: a 1:1 coarsened exact-matched controlled study

INTRODUCTION

The impact of liver cirrhosis on the difficulty of minimal invasive liver resection (MILR) remains controversial and current difficulty scoring systems do not take in to account the presence of cirrhosis as a significant factor in determining the difficulty of MILR. We hypothesized that the difficulty of MILR is affected by the presence of cirrhosis. Hence, we performed a 1:1 matched-controlled study comparing the outcomes between patients undergoing MILR with and without cirrhosis including the Iwate system and Institut Mutualiste Montsouris (IMM) system in the matching process.

METHODS

Between 2006 and 2019, 598 consecutive patients underwent MILR of which 536 met the study inclusion criteria. There were 148 patients with cirrhosis and 388 non-cirrhotics. One-to-one coarsened exact matching identified approximately exact matches between 100 cirrhotic patients and 100 non-cirrhotic patients.

RESULTS

Comparison between MILR patients with cirrhosis and non-cirrhosis in the entire cohort demonstrated that patients with cirrhosis were associated with a significantly increased open conversion rate, transfusion rate, need for Pringles maneuver, postoperative, stay, postoperative morbidity and postoperative 90-day mortality. After 1:1 coarsened exact matching, MILR with cirrhosis were significantly associated with an increased open conversion rate (15% vs 6%, p = 0.03), operation time (261 vs 238 min, p  < 0.001), blood loss (607 vs 314 mls, p  = 0.002), transfusion rate (22% vs 9%, p  = 0.001), need for application of Pringles maneuver (51% vs 34%, p  = 0.010), postoperative stay (6 vs 4.5 days, p  = 0.004) and postoperative morbidity (26% vs 13%, p  = 0.029).

CONCLUSION

The presence of liver cirrhosis affected both the intraoperative technical difficulty and postoperative outcomes of MILR and hence should be considered an important parameter to be included in future difficulty scoring systems for MILR.

Retroperitoneal laparoscopic hepatectomy of recurrent hepatocellular carcinoma: case report and literature review

BACKGROUND

Almost all liver tumours can be removed laparoscopically, but some difficult tumour locations complicate laparoscopic surgery. Recurrent liver tumours often pose great difficulties to laparoscopic surgery due to adhesions caused by previous operations. Referring to laparoscopic adrenalectomy, a retroperitoneal approach is proposed to remove liver tumours near the adrenal gland, which will provide a new method for liver surgery.

CASE PRESENTATION

Our case involves a patient with recurrent hepatocellular carcinoma (HCC) whose last operation was laparoscopic hepatectomy in our department, with a recurrence of HCC 2 years after the first surgery. In this case, based on preoperative CT and MRI, through a retroperitoneal approach, combined with intraoperative ultrasound (IOUS) localization and indocyanine green (ICG) fluorescence navigation, laparoscopic hepatectomy was successfully performed to precisely resect recurrent hepatocellular carcinoma in segment VII. The patient was discharged on the third day after the operation. The AFP decreased to normal levels on the 28th postoperative day.

CONCLUSIONS

Retroperitoneal hepatectomy has the advantages of less trauma, shorter operation times, fewer complications and faster recovery for hepatic tumours near the adrenal gland. Accurate localization of tumours is needed to ensure accurate resection; therefore, IOUS and ICG fluorescence are very important. Liver parenchyma was severed strictly according to fluorescent labelling during hepatectomy, which prevented the deviation of liver parenchyma from the plane and ensured that the margin of hepatectomy was tumour-free. In order to ensure a radical resection of the tumour, it may be necessary to enter the abdominal cavity.

Stepwise development of laparoscopic liver resection skill using rubber traction technique

BACKGROUND

To improve patient safety, we standardized our surgical technique and implemented a stepwise strategy for surgeons learning to perform laparoscopic liver resection (LLR). The aim of the study is to describe how the stepwise training approach and standardized LLR affects surgical outcomes.

METHODS

Data from 272 consecutive patients who underwent LLR from January 2009 to December 2017 were retrospectively reviewed. The risk-adjusted cumulative sum (RA-CUSUM) of surgical failures (conversion to laparotomy, blood transfusion, or Clavien-Dindo grade ≥3) and the CUSUM of operative time were used to determine optimal number of operations needed to achieve the best surgical outcome.

RESULTS

As the surgeon moved from simple to complex procedures, the complication rates, need for transfusions, and conversion rates did not increase over time. After 53 cases of minor LLR, a learning curve of 21 cases was achieved for right hepatectomy. Blood loss and operative time significantly improved thereafter. For minor anterolateral and posterosuperior segment resections, blood loss, and operative time significantly improved at the 37th and 31st case, respectively, given that the anterolateral segments had more complex surgeries performed.

CONCLUSION

Standardization of the operative technique and the implementation of a stepwise approach to training surgeons to perform LLRs could considerably improve surgical outcomes.

Learning Curve in Laparoscopic Liver Resection, Educational Value of Simulation and Training Programmes: A Systematic Review

BACKGROUND

The laparoscopic approach is widely accepted as the procedure of choice for abdominal surgery. However, laparoscopic liver resection (LLR) has advanced slowly due to the significant learning curve (LC), and only few publications have dealt with advanced training in LLR.

METHODS

Two reviewers conducted systematic research through MEDLINE and EMBASE with combinations of the following keywords: (learning curve OR teaching OR training OR simulation OR education) AND (liver OR hepatic) AND (laparoscopic OR laparoscopy). Robotic-assisted, hand-assisted and hybrid LLRs were excluded.

RESULTS

Nineteen studies were retrieved. Overall, the level of evidence was low. Thirteen articles assessed the LC during real-life LLR, and six articles focussed on simulation and training programmes in LLR. The LC in minor LLR comprised 60 cases overall, and 15 cases for standardised left lateral sectionectomy. For major LLR (MLLR), the LC was 50 cases for most studies, but was reported to be 15-20 cases in more recent studies, provided MLLR is performed progressively in selected patients. However, there was heterogeneity in the literature regarding the number of minor LLRs required before MLLR, with 60 minor LLRs reported as the minimum. Six studies showed a potential benefit of simulation and training programmes in this field. The gradual implementation of LLR combined with simulation-based training programmes could reduce the clinical impact of LC.

CONCLUSIONS

The LC in LLR is a long process, and MLLR should be gradually implemented under the supervision of experienced surgeons. Training outside the operating room may reduce the LC in real-life situations.

Predictive ability of preoperative CT scan for the intraoperative difficulty and postoperative outcomes of laparoscopic liver resection

BACKGROUND

The surgical difficulty and postoperative outcomes of laparoscopic liver resection (LLR) are related to the size of the cut liver surface. This study assessed whether the estimated parenchymal transection surface area could predict intraoperative difficulty and postoperative outcomes.

METHODS

LLRs performed between 2008 and 2018, for whom a preoperative CT scan was available for 3D review, were included in the study. The area of scheduled parenchymal transection was measured on the preoperative CT scan and cut-off values that could predict intraoperative difficulty were analyzed.

RESULTS

152 patients who underwent left lateral sectionectomy (n = 27, median estimated area 30.1 cm² [range 16.6-65.9]), left/right hepatectomy (n = 17 and n = 70, 76.8 cm² [range 43.9-150.9] and 72.2 cm² [range 39.4-124.9], respectively), right posterior sectionectomy (n = 7, 113.3 cm² [range 102.1-136.3]), central hepatectomy (n = 11, 109.1 cm² [range 66.1-186.1]) and extended left/right hepatectomy (n = 6 and n = 14, 115.3 cm² [range 92.9-128.9] and 50.7 cm² [range 13.3-74.9], respectively) were included. An estimated parenchymal transection surface area ≥ 100 cm² was associated with significant increase in operative time (AUC 0.81, 95% CI [0.70, 0.93], p < 0.001) and estimated blood loss (AUC 0.92, 95% CI [0.86, 0.97], p < 0.001), as well as a higher conversion rate (22.2% vs. 4.0%, p < 0.001). Overall (p = 0.017) and major morbidity (p = 0.003), biliary leakage (p < 0.001) and pulmonary complications (p < 0.001) were significantly higher in patients with an estimated parenchymal transection surface area ≥ 100 cm².

CONCLUSIONS

An estimated parenchymal transection surface area ≥ 100 cm² is a relevant indicator of surgical difficulty and postoperative complications in LLR.

Implementation and outcome of minor and major minimally invasive liver surgery in the Netherlands

BACKGROUND

While most of the evidence on minimally invasive liver surgery (MILS) is derived from expert centers, nationwide outcomes remain underreported. This study aimed to evaluate the implementation and outcome of MILS on a nationwide scale.

METHODS

Electronic patient files were reviewed in all Dutch liver surgery centers and all patients undergoing MILS between 2011 and 2016 were selected. Operative outcomes were stratified based on extent of the resection and annual MILS volume.

RESULTS

Overall, 6951 liver resections were included, with a median annual volume of 50 resections per center. The overall use of MILS was 13% (n = 916), which varied from 3% to 36% (P < 0.001) between centers. The nationwide use of MILS increased from 6% in 2011 to 23% in 2016 (P < 0.001). Outcomes of minor MILS were comparable with international studies (conversion 0-13%, mortality <1%). In centers which performed ≥20 MILS annually, major MILS was associated with less conversions (14 (11%) versus 41 (30%), P < 0.001), shorter operating time (184 (117-239) versus 200 (139-308) minutes, P = 0.010), and less overall complications (37 (30%) versus 58 (42%), P = 0.040).

CONCLUSION

The nationwide use of MILS is increasing, although large variation remains between centers. Outcomes of major MILS are better in centers with higher volumes.

Evaluating the learning curve for laparoscopic liver resection: a comparative study between standard and learning curve CUSUM

BACKGROUND

Laparoscopic liver resection (LLR) requires training in both hepatobiliary surgery and advanced laparoscopy. Available data on LLR learning curves are derived from pioneer surgeons. The aims of this study were to evaluate the LLR learning curve for second generation surgeons, and to compare different CUSUM methodology with and without risk adjustment.

METHODS

Retrospective analysis of a prospective database of 111 consecutive patients who underwent LLR by two surgeons at a single centre between 2011 and 2016. The LLR learning curve for minor hepatectomy (MH) was evaluated for each surgeon using standard CUSUM before and after risk-adjusting for operative difficulty using the Iwate index, and compared with Learning Curve (LC) CUSUM. The end points were operative time and conversion rate.

RESULTS

Standard CUSUM analysis identified a learning curve of 50-60 MH procedures. The corresponding learning curve reduced to 25-30 after risk-adjusting for operative difficulty, whilst LC-CUSUM identified a learning curve of 17-25 procedures.

CONCLUSIONS

The learning curve for laparoscopic minor liver resection by second generation surgeons is shorter than that for pioneer surgeons. Laparoscopic HPB fellowship programmes may further shorten the learning curve, facilitating safe expansion of LLR. The LC-CUSUM method is an alternative technique that warrants further study.

Laparoscopic Liver Resection: Experience of 436 Cases in One Center

BACKGROUND

To report experience of laparoscopic liver resection (LLR) in one center.

METHODS

We retrospectively reviewed 436 consecutive LLRs in 411 patients between December 2010 and December 2016. On the basis of the 2008 Louisville Statement, we divided the 436 cases into two groups: Simple Group (n = 203) and Difficult Group (n = 233).

RESULTS

The indications were HCC (n = 194), colorectal cancer liver metastasis (n = 156), benign tumors (n = 62), hepatolithiasis (n = 2), and other malignant lesions (n = 22). The median tumor size was 24 mm (range 3 to 130). Procedures of LLR included wedge resection (n = 230), one segmentectomy (n = 8), two segmentectomies (n = 12), left lateral sectionectomy (n = 75), right hepatectomy (n = 52), left hepatectomy (n = 31), extended right hepatectomy (n = 2), extended left hepatectomy (n = 5), central bisectionectomy (n = 3), right posterior sectionectomy (n = 12), and right anterior sectionectomy (n = 6). The median operative time was 228 min (range 9-843) and median blood loss was 150 ml (range 2-3500). Twenty-five cases required blood transfusion (5.7%). Conversion to open surgery was required in six cases (1.4%). The mean length of stay was 6.4 ± 2.9 days. Overall complication rate was 9.4% and major complication rate was 5%. One patient died of liver failure on the thirtieth postoperative day after a right hepatectomy. We had higher median blood loss (200 vs. 100 ml; p < 0.001), higher transfusion rate (8.2 vs. 2.9%; p = 0.020), longer median operative time (297 vs. 164 min; p < 0.001), higher conversion rate (2.6 vs. 0%; p = 0.021), higher complication rate (14.2 vs. 3.9%; p < 0.001), and longer mean postoperative hospital stay (6.8 ± 2.9 vs. 5.9 ± 3.0 days; p < 0.001) in the Difficult Group.

CONCLUSIONS

Laparoscopic liver resection is safe for selected patients in the Difficult Group. On the basis of the 2008 Louisville Statement, selection criteria of LLR are helpful to predict the difficulty of the operation and the postoperative outcomes of LLR.

Multicentre propensity score-matched study of laparoscopic versus open repeat liver resection for colorectal liver metastases

BACKGROUND

Repeat liver resection is often the best treatment option for patients with recurrent colorectal liver metastases (CRLM). Repeat resections can be complex, however, owing to adhesions and altered liver anatomy. It remains uncertain whether the advantages of a laparoscopic approach are upheld in this setting. The aim of this retrospective, propensity score-matched study was to compare the short-term outcome of laparoscopic (LRLR) and open (ORLR) repeat liver resection.

METHODS

A multicentre retrospective propensity score-matched study was performed including all patients who underwent LRLRs and ORLRs for CRLM performed in nine high-volume centres from seven European countries between 2000 and 2016. Patients were matched based on propensity scores in a 1 : 1 ratio. Propensity scores were calculated based on 12 preoperative variables, including the approach to, and extent of, the previous liver resection. Operative outcomes were compared using paired tests.

RESULTS

Overall, 425 repeat liver resections were included. Of 271 LRLRs, 105 were matched with an ORLR. Baseline characteristics were comparable after matching. LRLR was associated with a shorter duration of operation (median 200 (i.q.r. 123-273) versus 256 (199-320) min; P < 0·001), less intraoperative blood loss (200 (50-450) versus 300 (100-600) ml; P = 0·077) and a shorter postoperative hospital stay (5 (3-8) versus 6 (5-8) days; P = 0·028). Postoperative morbidity and mortality rates were similar after LRLR and ORLR.

CONCLUSION

LRLR for CRLM is feasible in selected patients and may offer advantages over an open approach.

Contemporary practice and short-term outcomes after liver resections in a complete national cohort

BACKGROUND

Improved outcome after liver resections have been reported in several series, but outcomes from national cohorts are scarce. Our aim was to evaluate nationwide practice and short-term outcomes after liver surgery in a universal healthcare system.

METHODS

A complete 5-year cohort of all liver resections from the Norwegian Patient Registry (NPR). Short-term outcomes were aggregated length of stay (a-LoS), reoperation and 90-day mortality.

RESULTS

Of 2118 liver resections, 605 (28.6%) were major, median age was 65 years and 1184 (55%) were male. Most common indication was metastatic disease (n = 1554; 73.4%) and primary malignancy (n = 328; 15.3%). Laparoscopy was performed in 513 (33.9%) of minor and 37 (6.1%) of major liver resections and increased over time to 39.1% of minor resections in 2016. Median a-LoS was 12 days for major resections, 8 days for open minor and 3 days for laparoscopic minor resections. Reoperation was reported for 159 (7.4%) and 90-day mortality for 44 (2.1%). Primary malignancy, male gender, elderly patients and major resections were associated with poorer outcome.

CONCLUSIONS

In a national cohort, laparoscopy is used for a substantial proportion of minor resections and was associated with reduced a-LoS. Risk factors for reoperation and mortality were male gender, increased age and major resection for primary malignancy.

Laparoscopic liver resection: a review of current indications and surgical techniques

Laparoscopic liver resection (LLR) has been the most impressive development in the field of liver surgery in recent two decades. Technical innovations and experience accumulation have made LLR a safe and effective procedure with faster postoperative recovery. Despite the fast spreading of the procedure, details regarding the indications, oncological outcomes and technical essentials were still disputable. To address these issues, two international consensus conferences were hold to update the knowledge in this field. The statements of the both conferences were not conclusive and more high-quality researches are required. In this article, we reviewed the development and the current state of LLR. Indications, outcomes, surgical techniques and devices used in LLR were also discussed.