Risk Factors of Positive Resection Margin in Laparoscopic and Open Liver Surgery for Colorectal Liver Metastases: A New Perspective in the Perioperative Assessment A European Multicenter Study

Outpatient and Ambulatory Extended Recovery Robotic Hepatectomy: Multinational Study of 307 Cases

BACKGROUND

For open minor hepatectomy, morbidity and recovery are dominated by the incision. The robotic approach may transform this "incision dominant procedure" into a safe outpatient procedure.

STUDY DESIGN

We audited outpatient (less than 2 midnights) robotic hepatectomy at 6 hepatobiliary centers in 2 nations to test the hypothesis that the robotic approach can be a safe and effective short-stay procedure. Establishing early recovery after surgery programs were active at all sites, and home digital monitoring was available at 1 of the institutions.

RESULTS

A total of 307 outpatient (26 same-day and 281 next-day discharge) robotic hepatectomies were identified (2013 to 2023). Most were minor hepatectomies (194 single segments, 90 bi-segmentectomies, 14 three segments, and 8 four segments). Thirty-nine (13%) were for benign histology, whereas 268 were for cancer (33 hepatocellular carcinoma, 27 biliary, and 208 metastatic disease). Patient characteristics were a median age of 60 years (18 to 93 years), 55% male, and a median BMI of 26 kg/m 2 (14 to 63 kg/m 2 ). Thirty (10%) patients had cirrhosis. One hundred eighty-seven (61%) had previous abdominal operation. Median operative time was 163 minutes (30 to 433 minutes), with a median blood loss of 50 mL (10 to 900 mL). There were no deaths and 6 complications (2%): 2 wound infections, 1 failure to thrive, and 3 perihepatic abscesses. Readmission was required in 5 (1.6%) patients. Of the 268 malignancy cases, 25 (9%) were R1 resections. Of the 128 with superior segment resections (segments 7, 8, 4A, 2, and 1), there were 12 positive margins (9%) and 2 readmissions for abscess.

CONCLUSIONS

Outpatient robotic hepatectomy in well-selected cases is safe (0 mortality, 2% complication, and 1.6% readmission), including resection in the superior or posterior portions of the liver that is challenging with nonarticulating laparoscopic instruments.

Laparoscopically Limited Anatomic Liver Resections: A Single-Center Analysis for Oncologic Outcomes of the Conceptual Procedure

BACKGROUND

Limited anatomic resections (LARs), such as segmentectomies, performed using a fully laparoscopic approach, have gained popularity for liver malignancies. However, the oncologic efficacy of laparoscopic LARs (Lap-LARs) needs further investigation. This cohort study evaluated the oncologic outcomes of Lap-LAR for hepatocellular carcinoma (HCC) and colorectal liver metastasis (CRLM).

METHODS

At a Japanese referral center, 112 patients underwent Lap-LAR using the Glissonean approach and indocyanine green (ICG) fluorescence navigation. Recurrence-free survival (RFS), overall survival (OS), time to interventional failure (TIF), and time to surgical failure (TSF) were assessed.

RESULTS

Among the 112 patients (median age, 74 years [range, 66-80 years]; 80 men [71.4 %]), Lap-LAR showed promising results. The median operative time was 348 min (range, 280-460 min), and the median blood loss was 190 mL (range, 95.5-452.0 mL). The median error between the estimated and actual liver volumes was 2 % (1.2-4.8 %). Complications greater than Clavien-Dindo 3a were observed in 11.6 % of the patients. The 5-year RFS, OS, and TIF rates for HCC were 45.1 % ± 7.9 %, 73.1 % ± 6.7 %, and 74.2 % ± 6 .6 %, respectively. The 5-year RFS, OS, and TSF rates for CRLM were 36.8 % ± 8.7 %, 60.1 % ± 13.3 %, and 63.6 % ± 10.4 %, respectively.

CONCLUSIONS

Lap-LAR showed favorable oncologic outcomes for HCC and CRLM. Its precise technique makes it a promising therapeutic option for liver malignancies. Further comparisons with conventional approaches are warranted.

Prevention of Post-Hepatectomy Liver Failure in Cirrhotic Patients Undergoing Minimally Invasive Liver Surgery for HCC: Has the Round Ligament to Be Preserved?

Post-hepatectomy liver failure (PHLF) represents a major cause of morbidity and mortality after liver resection. The factors related to PHLF are represented not only by the volume and function of the future liver remnant but also by the severity of portal hypertension. The aim of this study was to assess whether the preservation of the round ligament (RL) may mitigate portal hypertension, thus decreasing the risk of PHLF and ascites in cirrhotic patients while undergoing minimally invasive liver surgery (MILS). All the cirrhotic patients who underwent MILS for HCC from 2016 to 2021 in two international tertiary referral centers were retrospectively analyzed, comparing cases with the RL preserved vs. those with the RL divided. Only patients with cirrhosis ≥ Child A6, portal hypertension, and ICG-R15 > 10% were included. Main postoperative outcomes were compared, and the risk factors for postoperative ascites (severe PHLF, grade B/C) were investigated through a logistic regression. After the application of the selection criteria, a total of 130 MILS patients were identified, with 86 patients with the RL preserved and 44 with the RL divided. The RL-preserved group showed lower incidences of severe PHLF (7.0% vs. 20.5%, p = 0.023) and ascites (5.8% vs. 18.2%, p = 0.026) in comparison with the RL-divided group. After uni/multivariate analysis, the risk factors related to postoperative ascites were RL division and platelets < 92 × 103/µL, calculated with ROC analysis. The preservation of the round ligament during MILS may mitigate portal hypertension, preventing PHLF and ascites in cirrhotic patients with borderline liver function.

Donor Safety and Risk Factors of Pure Laparoscopic Living Donor Right Hepatectomy: A Korean Multicenter Study

OBJECTIVE

The aim of this study was to identify safety and risk factors of living donor after pure laparoscopic donor right hepatectomy in a Korean multicenter cohort study.

BACKGROUND

Pure laparoscopic donor right hepatectomy is not yet a standardized surgical procedure due to lack of data.

METHODS

This retrospective study included 543 patients undergoing PLRDH between 2010 and 2018 in 5 Korean transplantation centers. Complication rates were assessed and multivariate logistic regression analyses were performed to identify risk factors of open conversion, overall complications, major complications, and biliary complications.

RESULTS

Regarding open conversion, the incidence was 1.7% and the risk factor was body mass index >30 kg/m 2 [ P =0.001, odds ratio (OR)=22.72, 95% CI=3.56-146.39]. Rates of overall, major (Clavien-Dindo classification III-IV), and biliary complications were 9.2%, 4.4%, and 3.5%, respectively. For overall complications, risk factors were graft weight >700 g ( P =0.007, OR=2.66, 95% CI=1.31-5.41), estimated blood loss ( P <0.001, OR=4.84, 95% CI=2.50-9.38), and operation time >400 minutes ( P =0.01, OR=2.46, 95% CI=1.25-4.88). For major complications, risk factors were graft weight >700 g ( P =0.002, OR=4.01, 95% CI=1.67-9.62) and operation time >400 minutes ( P =0.003, OR=3.84, 95% CI=1.60-9.21). For biliary complications, risk factors were graft weight >700 g ( P =0.01, OR=4.34, 95% CI=1.40-13.45) and operation time >400 minutes ( P =0.01, OR=4.16, 95% CI=1.34-12.88).

CONCLUSION

Careful donor selection for PLRDH considering body mass index, graft weight, estimated blood loss, and operation time combined with skilled procedure can improve donor safety.

Risk Factors of Positive Resection Margin in Hepatectomy for Resectable Ruptured Hepatocellular Carcinoma: Risk Prediction and Prognosis

BACKGROUND AND AIM

Clinical work has revealed that hepatectomy for resectable ruptured hepatocellular carcinoma (rHCC) has a relatively high percentage of positive resection margins found in postoperative pathology. It is necessary to evaluate the risk factors associated with R1 resection in patients undergoing hepatectomy for rHCC.

METHODS

A total of 408 patients with resectable rHCC originating from three centers undergoing surgery from January 2012 to January 2020 were consecutively enrolled in the study to study the prognostic impact of R1 resection using Kaplan-Meier plotting of survival curves. One center with 280 served as the training group, and the other two centers served as the validation group. Multivariate logistic regression analysis screened for variables affecting R1 and developed prediction models, and the models were tested in the validation cohort using the receiver operating characteristic curves (ROC) and calibration curves.

RESULTS

The prognosis of rHCC patients with positive cut margins was worse than that of patients with R0 resection. Risk factors for R1 resection were tumor max length (OR = 2.668 [1.161-6.131]), microvascular invasion (MVI) (OR = 3.655 [1.766-7.566]), times of hepatic inflow occlusion (1/0:OR = 2.213 [1.113-4.399]; 2/0:OR = 5.723 [2.010-8.289]) and timing of hepatectomy (OR = 5.284 [2.394-9.661]), using tumor max length, times of HIO, and timing of hepatectomy to construct the nomogram, the area under the curve of the model was 0.810 (0.781-0.842) and 0.782 (0.752-0.805) in the training and validation groups, respectively, and the calibration curve of the model was basically on the 45° line.

CONCLUSIONS

This study constructs a clinical model to predict R1 resection after hepatectomy for resectable rHCC, which can be used to better plan perioperative strategies for the incidence of R1 resection during hepatectomy.

The Value of Indocyanine Green Image-Guided Surgery in Patients with Primary Liver Tumors and Liver Metastases

INTRODUCTION

Successful R0 resection is crucial for the survival of patients with primary liver cancer (PLC) or liver metastases. Up to date, surgical resection lacks a sensitive, real-time intraoperative imaging modality to determine R0 resection. Real-time intraoperative visualization with near-infrared light fluorescence (NIRF) using indocyanine green (ICG) may have the potential to meet this demand. This study evaluates the value of ICG visualization in PLC and liver metastases surgery regarding R0 resection rates.

MATERIALS AND METHODS

Patients with PLC or liver metastases were included in this prospective cohort study. ICG 10 mg was administered intravenously 24 h before surgery. Real-time intraoperative NIRF visualization was created with the Spectrum^TM fluorescence imaging camera system. First, all liver segments were inspected with the fluorescence imaging system and intraoperative ultrasound for identification of the known tumor, as well as additional lesions, and were compared to preoperative MRI images. PLC, liver metastases, and additional lesions were then resected according to oncological principles. In all resected specimens, the resection margins were analyzed with the fluorescence imaging system for ICG-positive spots immediately after resection. Histology of additional detected lesions, as well as ICG fluorescence compared to histological resection margins, were assessed.

RESULTS

Of the 66 included patients, median age was 65.5 years (IQR 58.7-73.9), 27 (40.9%) were female, and 18 (27.3%) were operated on laparoscopically. Additional ICG-positive lesions were detected in 23 (35.4%) patients, of which 9 (29%) were malignant. In patients with no fluorescent signal at the resection margin, R0 rate was 93.9%, R1 rate was 6.1%, and R2 rate was 0% compared to an ICG-positive resection margin with an R0 rate of 64.3%, R1 rate of 21.4%, and R2 rate of 14.3% (p = 0.005). One- and two-year overall survival rates were 95.2% and 88.4%, respectively.

CONCLUSION

The presented study provides significant evidence that ICG NIRF guidance helps to identify R0 resection intraoperatively. This offers true potential to verify radical resection and improve patient outcomes. Furthermore, implementation of NIRF-guided imaging in liver tumor surgery allows us to detect a considerable amount of additional malignant lesions.

An International Expert Delphi Consensus on Defining Textbook Outcome in Liver Surgery (TOLS)

OBJECTIVE

To reach global expert consensus on the definition of TOLS in minimally invasive and open liver resection among renowned international expert liver surgeons using a modified Delphi method.

BACKGROUND

Textbook outcome is a novel composite measure combining the most desirable postoperative outcomes into one single measure and representing the ideal postoperative course. Despite a recently developed international definition of Textbook Outcome in Liver Surgery (TOLS), a standardized and expert consensus-based definition is lacking.

METHODS

This international, consensus-based, qualitative study used a Delphi process to achieve consensus on the definition of TOLS. The survey comprised 6 surgical domains with a total of 26 questions on individual surgical outcome variables. The process included 4 rounds of online questionnaires. Consensus was achieved when a threshold of at least 80% agreement was reached. The results from the Delphi rounds were used to establish an international definition of TOLS.

RESULTS

In total, 44 expert liver surgeons from 22 countries and all 3 major international hepato-pancreato-biliary associations completed round 1. Forty-two (96%), 41 (98%), and 41 (98%) of the experts participated in round 2, 3, and 4, respectively. The TOLS definition derived from the consensus process included the absence of intraoperative grade ≥2 incidents, postoperative bile leakage grade B/C, postoperative liver failure grade B/C, 90-day major postoperative complications, 90-day readmission due to surgery-related major complications, 90-day/in-hospital mortality, and the presence of R0 resection margin.

CONCLUSIONS

This is the first study providing an international expert consensus-based definition of TOLS for minimally invasive and open liver resections by the use of a formal Delphi consensus approach. TOLS may be useful in assessing patient-level hospital performance and carrying out international comparisons between centers with different clinical practices to further improve patient outcomes.

Role of preoperative 3D rendering for minimally invasive parenchyma sparing liver resections

BACKGROUND

3D rendering (3DR) represents a promising approach to plan surgical strategies. The study aimed to compare the results of minimally invasive liver resections (MILS) in patients with 3DR versus conventional 2D CT-scan.

METHODS

We performed 118 3DR for various indications; the patients underwent a preoperative tri-phasic CT-scan and rendered with Synapse3D® Software. Fifty-six patients undergoing MILS with pre-operative 3DR were compared to a similar cohort of 127 patients undergoing conventional pre-operative 2D CT-scan using the propensity score matching (PSM) analysis.

RESULTS

The 3DR mandated pre-operative surgical plan variations in 33.9% cases, contraindicated surgery in 12.7%, providing a new surgical indication in 5.9% previously excluded cases. PSM identified 39 patients in both groups with comparable results in terms of conversion rates, blood loss, blood transfusions, parenchymal R1-margins, grade ≥3 Clavien-Dindo complications, 90-days mortality, and hospital stay respectively in 3DR and conventional 2D. Operative time was significantly increased in the 3DR group (402 vs. 347 min, p = 0.020). Vascular R1 resections were 25.6% vs 7.7% (p = 0.068), while the conversion rate was 0% vs 10.2% (p = 0.058), respectively, for 3DR group vs conventional 2D.

CONCLUSION

3DR may help in surgical planning increasing resectability rate while reducing conversion rates, allowing the precise identification of anatomical landmarks in minimally invasive parenchyma-preserving liver resections.

Safety and Feasibility of Laparoscopic Right or Extended Right Hemi Hepatectomy Following Modulation of the Future Liver Remnant in Patients with Colorectal Liver Metastases: A Systematic Review

Background: Major hepatectomies after future liver remnant (FLR) modulation are technically demanding procedures, especially when performed as minimally invasive surgery. The aim of this systematic review is to assess current evidence regarding the safety and feasibility of laparoscopic right or extended right hemihepatectomies after FLR modulation. Materials and Methods: The Medline, PubMed, Cochrane Library, and Embase databases were searched for studies involving laparoscopic right or extended right hemihepatectomies after FLR modulation, from their inception to December 2021. Two reviewers independently selected eligible articles and assessed their quality using the Newcastle-Ottawa Quality Assessment Scale (NOS). Baseline characteristics and outcomes were extracted from the included studies and summarized. Results: Six studies were included. In these studies, the median length of stay after the second stage ranged from 4.5 to 15.5 days and postoperative complication rates between 4.5% and 42.8%. Overall, 7.4% of patients developed liver failure, and 90-day mortality occurred in 3.2% of patients. The R0 resection rate was 93.5%. Only one study reported long-term outcomes, describing comparable 3-year overall survival rates following laparoscopic and open surgery (80% versus 54%, P = .154). Conclusions: The current evidence is scarce, but it suggests that in experienced centers, laparoscopic right or extended right hemihepatectomy, following FLR modulation, is a safe and feasible procedure.

Outcomes and Patient Selection in Laparoscopic vs. Open Liver Resection for HCC and Colorectal Cancer Liver Metastasis

Hepatocellular carcinoma (HCC) and colorectal liver metastasis (CRLM) are the two most common malignant tumors that require liver resection. While liver transplantation is the best treatment for HCC, organ shortages and high costs limit the availability of this option for many patients and make resection the mainstay of treatment. For patients with CRLM, surgical resection with negative margins is the only potentially curative option. Over the last two decades, laparoscopic liver resection (LLR) has been increasingly adopted for the resection of a variety of tumors and was found to have similar long-term outcomes compared to open liver resection (OLR) while offering the benefits of improved short-term outcomes. In this review, we discuss the current literature on the outcomes of LLR vs. OLR for patients with HCC and CRLM. Although the use of LLR for HCC and CRLM is increasing, it is not appropriate for all patients. We describe an approach to selecting patients best-suited for LLR. The four common difficulty-scoring systems for LLR are summarized. Additionally, we review the current evidence behind the emerging robotically assisted liver resection technology.

[Indocyanine green in liver tumor resection]

Primary liver cancer and colorectal cancer liver metastases are among the leading causes of cancer-related mortality worldwide. Surgery is one of the main methods of treatment to achieve the best results in overall and recurrence-free survival. The main objectives in this surgery are preoperative planning, assessment of functional viability of liver parenchyma and total resection with low complication rate. Post-resection liver failure is one of the most formidable and often fatal complication following functional failure of liver remnant. Thus, preoperative assessment of liver functional reserves is a necessary step for adequate selection of patients and safe surgery. Passive liver tests, such as biochemical parameters or clinical scales, do not accurately reflect the actual functional component of liver parenchyma. The most accurate method is dynamic quantitative test of liver, such as indocyanine green clearance. The authors discuss the practical aspects of preoperative assessment of liver functional reserves using indocyanine green, as well as the concept and technical foundations of fluorescent imaging in hepatobiliary surgery.

Colorectal Cancer Liver Metastases: Is an R1 Hepatic Resection Accepted?

Metastatic colorectal cancer is associated with a rather dismal 5-year overall survival. The liver is the most commonly affected organ. Improved 5-year survival rates after successful hepatic resections for metastases confined to the liver have been reported. Certainly, a hepatectomy that results in an incomplete tumor resection, in terms of leaving macroscopic residual tumor in the future liver remnant, is not associated with survival benefits. However, the prognostic implications of a microscopically positive surgical margin or a clear margin of less than 1 mm (R1) on pathology are debatable. Although it has been a field of extensive research, the relevant literature often reports contradictory results. The purpose of the present study was to define, assess the risk factors for, and, ultimately, analyze the effect that an R1 hepatic resection for colorectal cancer liver metastases might have on local recurrence rates and long-term prognosis by reviewing the relevant literature. Achieving an R0 hepatic resection, optimally with more than 1 mm of clear margin, should always be the goal. However, in the era of the aggressive multimodality treatment of liver metastatic colorectal cancer, an R1 resection might be the cost of increasing the pool of patients finally eligible for resection. The majority of literature reports have highlighted the detrimental effect of R1 resections on local recurrence and overall survival. However, there are indeed studies that degraded the prognostic handicap as a consequence of an R1 resection in selected patients and highlighted the presence of RAS mutations, the response to chemotherapy, and, in general, factors that reflect the biology of the disease as important, if not the determinant, prognostic factors. In these patients, the aggressive disease biology seems to outperform the resection margin status as a prognostic factor, and the recorded differences between R1 and R0 resections are equalized. Properly and accurately defining this patient group is a future challenge in the field of the surgical treatment of colorectal cancer liver metastases.

Indocyanine Green Fluorescence Navigation in Liver Surgery: A Systematic Review on Dose and Timing of Administration

BACKGROUND

Indocyanine green (ICG) fluorescence has proven to be a high potential navigation tool during liver surgery; however, its optimal usage is still far from being standardized.

METHODS

A systematic review was conducted on MEDLINE/PubMed for English articles that contained the information of dose and timing of ICG administration until February 2021. Successful rates of tumor detection and liver segmentation, as well as tumor/patient background and imaging settings were also reviewed. The quality assessment of the articles was performed in accordance with the Scottish Intercollegiate Guidelines Network (SIGN).

RESULTS

Out of initial 311 articles, a total of 72 manuscripts were obtained. The quality assessment of the included studies revealed usually low; only 9 articles got qualified as high quality. Forty articles (55%) focused on open resections, whereas 32 articles (45%) on laparoscopic and robotic liver resections. Thirty-four articles (47%) described tumor detection ability, and 25 articles (35%) did liver segmentation ability, and the others (18%) did both abilities. Negative staining was reported (42%) more than positive staining (32%). For tumor detection, majority used the dose of 0.5 mg/kg within 14 days before the operation day, and an additional administration (0.02-0.5 mg/kg) in case of longer preoperative interval. Tumor detection rate was reported to be 87.4% (range, 43%-100%) with false positive rate reported to be 10.5% (range, 0%-31.3%). For negative staining method, the majority used 2.5 mg/body, ranging from 0.025 to 25 mg/body. For positive staining method, the majority used 0.25 mg/body, ranging from 0.025 to 12.5 mg/body. Successful segmentation rate was 88.0% (range, 53%-100%).

CONCLUSION

The time point and dose of ICG administration strongly needs to be tailored case by case in daily practice, due to various tumor/patient backgrounds and imaging settings.

Outcome of major hepatectomy in cirrhotic patients; does surgical approach matter? A propensity score matched analysis

OBJECTIVE

Major hepatectomy in cirrhotic patients still represents a great challenge for liver surgeons. Hence, the aim in the present study is to investigate the clinical impact of major hepatectomy and to assess whether the surgical approach influences the outcome of cirrhotic patients.

METHODS

Multicenter retrospective study including cirrhotic patients undergoing major laparoscopic (mjLLR) and open liver resection (mjOLR) in 14 Western liver centers was performed (2009-2020). Clinical, demographic, and perioperative data were compared using propensity score matching (PSM). Long-term outcome after resection for hepatocellular carcinoma was analyzed.

RESULTS

Overall, 352 patients were included; 108 after mjLLR and 244 after mjOLR. After PSM, 88 patients were matched in each group. In the mjLLR group, compared to mjOLR, less blood loss (P = .042), lower overall and severe complication (P < .001, .020), such as surgical site infection, acute kidney injury and liver failure were observed, parallel to a shorter length of hospital stay. Stratifying patients based on the type of resection, less severe complications was observed only after laparoscopic left hepatectomy (P = .044), while the advantages of laparoscopy tend to decrease during right hepatectomy. Subgroup analysis of long-term survivals following liver resection for hepatocellular carcinoma showed no difference between mjLLR and mjOLR.

CONCLUSIONS

This multicenter experience suggests potential short-term benefits of mjLLR in cirrhotic patients compared to mjOLR, without compromising long-term outcome. These findings might have interesting clinical implications for the management of patients with chronic liver disease.

Assessment of Textbook Outcome in Laparoscopic and Open Liver Surgery

Importance

Textbook outcome (TO) is a composite measure that captures the most desirable surgical outcomes as a single indicator, yet to date TO has not been defined and assessed in the field of laparoscopic liver resection (LLR) and open liver resection (OLR).

Objective

To obtain international agreement on the definition of TO in liver surgery (TOLS) and to assess the incidence of TO in LLR and OLR in a large international multicenter database using a propensity-score matched analysis.

Design, Setting, and Participants

Patients undergoing LLR or OLR for all liver diseases between January 2011 and October 2019 were analyzed using a large international multicenter liver surgical database. An international survey was conducted among all members of the European-African Hepato-Pancreato-Biliary Association (E-AHPBA) and International Hepato-Pancreato-Biliary Association (IHPBA) to reach agreement on the definition of TOLS. The rate of TOLS was assessed for LLR and OLR before and after propensity-score matching. Factors associated with achieving TOLS were investigated.

Main Outcomes and Measures

Textbook outcome, with TOLS defined as the absence of intraoperative incidents of grade 2 or higher, postoperative bile leak grade B or C, severe postoperative complications, readmission within 30 days after discharge, in-hospital mortality, and the presence of R0 resection margin.

Results

A total of 8188 patients (4559 LLR; median age, 65 years [interquartile range, 55-73 years]; 2529 were male [55.8%] and 3629 OLR; median age, 64 years [interquartile range, 56-71 years]; 2204 were male [60.7%]) were included in the analysis of whom 69.1% achieved TOLS; 74.8% for LLR and 61.9% for OLR (P < .001). On multivariable analysis, American Society of Anesthesiologists grade III, previous abdominal surgery, histological diagnosis of colorectal liver metastases (odds ratio [OR], 0.656 [95% CI, 0.457-0.940]; P = .02), cholangiocarcinoma, non-CRLM, a tumor size of 30 mm or more, minor resection of posterior/superior segments (OR, 0.716 [95% CI, 0.577-0.887]; P = .002), anatomically major resection (OR, 0.579 [95% CI, 0.418-0.803]; P = .001), and nonanatomical resection (OR, 0.612 [95% CI, 0.476-0.788]; P < .001) were associated with a worse TOLS rate after LLR. For OLR, only histological diagnosis of cholangiocarcinoma (OR, 0.360 [95% CI, 0.214-0.607]; P < .001) and a tumor size of 30 mm or more (30-50 mm = OR, 0.718 [95% CI, 0.565-0.911]; P = .01; 50.1-100 mm = OR, 0.729 [95% CI, 0.554-0.960]; P = .02; >10 cm = OR, 0.550 [95% CI, 0.366-0.826]; P = .004) were associated with a worse TOLS rate.

Conclusions and Relevance

In this multicenter study, TOLS was found to be a useful tool for assessing patient-level hospital performance and may have utility in optimizing patient outcomes after LLR and OLR.

Prospective Non-Randomized Study of Intraoperative Assessment of Surgical Resection Margin of Colo-Rectal Liver Metastases

Introduction: More than 50% of patients with colorectal cancer (CRC) develop liver metastases during the natural course of disease. Surgical resection is currently the most potentially curative method in the treatment of colorectal liver metastases (CRLM). The goal of surgery is to achieve a negative resection margin (RM) of at least 1 mm, which provides the best prognosis for patients. The RM can be assessed by the pathologist of the resected liver specimen (RLS) and by the surgeon intraoperatively. The aim of this research paper is to determine the degree of agreement on intraoperative assessment of the RM by the surgeon and histopathological RM assessment by the pathologist.

Material and methods: This prospective non-randomized double-blind study was approved by the Ethics Committee of the Oncology Institute of Vojvodina and registered on ClinicalTrials.gov #NCT04634526. The study was conducted at the Oncology Institute of Vojvodina, Sremska Kamenica, Serbia. An experienced hepatobiliary surgeon assessed RM for every specimen intra-operatively, immediately after CRLM resection. Resected CRLM lesions were analyzed by two experienced pathologists. These data were compared with pathological RM assessment as a “gold standard”. RM of 1 mm or more was rated as negative RM (RM-). Disease-free survival (DFS) and recurrence rate was calculated by RM status defined by surgeon and by pathologist.

Results: From 01 January 2015 to 31 August 2019, 98 patients were enrolled in the study. There were 219 RLS with 245 CRLM. The surgeon registered positive RM (RM+) of <1mm in 41 (18.7%) RLS. Taking the result of the histopathological assessment (HPA) as the “gold standard”, it was determined that RM was true positive in 32 (14.6%) cases. False positive RM was found in 9 (4.1%) cases. False negative RM was found in 20 (9.1%) cases. True negative RM was found in 158 (72.2%) cases. Sensitivity of surgical assessment (SA) of RM+ was 61.5% (32/52). Specificity of SA of RM+ was 94.6% (158/167). The positive predictive value (PPV) was 78.0% (32/41), while the negative predictive value (NPV) was 88.8% (158/178). The overall accuracy of the RM+ SA was 86.8% (190/219). There was no statistically significant difference in the assessment of RM+ per RLS by surgeon and pathologists (p=0.061), but it was significant when analyses per patients was performed (p=0.017). Recurrence rate for RM+ patients was 48.1% (13/27, p=0.05) for SA and 35.0% (14/40, p=0.17) for HPA. Three year DFS for RM- and RM+ was 66.5% and 27.9% (p=0.04), respectively, by SA, and 64.8% and 42.1% (p=0.106), respectively, by HPA.

Conclusion: Intraoperative assessment of RM- by surgeon of RLS is clinically meaningful. There is not a statistically significant difference in the assessment of RM+ by surgeon and pathologists per RLS, but it was statically significant on a per patient basis. RM determined by surgeon has better prognostic impact on recurrence rate and 1- and 3-year DFS than standard histopathological assessment.

Evaluation of accuracy of laparoscopic liver mono-segmentectomy using the Glissonian approach with indocyanine green fluorescence negative staining by comparing estimated and actual resection volumes: A single-center retrospective cohort study

BACKGROUND/PURPOSE

Laparoscopic liver mono-segmentectomy (LLMS) may improve patient outcomes, but it is difficult and its accuracy and safety are unknown. We evaluated the accuracy of LLMS using Glissonian approach with indocyanine green fluorescence (ICG) negative staining.

METHODS

Seventy-four patients eligible for LLMS except for segment 1 were enrolled. Preoperative three-dimensional CT-based surgical simulation was used to determine estimated liver resection volume (ELRV), which was compared with modified actual liver resection volume (ALRV) obtained from actual liver resection mass. The LLMS accuracy was also evaluated based on operator's experience (attending surgeon [AS] or trainee surgeon [TS]).

RESULTS

Estimated liver resection volumes significantly correlated with ALRVs (r = .82) in all cases. Moreover, TS-conducted LLMS also showed acceptable difference between ELRV and ALRV compared with AS-conducted LLMS. There were no intergroup differences in estimated blood loss, operation time, time of Pringle maneuver, postoperative complications, and length of postoperative hospitalization (P < .05). Moreover, R0 resection was comparable between the AS and TS groups.

CONCLUSIONS

Laparoscopic liver mono-segmentectomy with Glissonian approach using ICG negative imaging ensured safe and accurate procedure owing to facilitated visualization of the resection line. Our approach was effective in avoiding postoperative liver dysfunction and securing radical resection. In addition, it might be helpful in TS education of LLMS.